Smartphone English Language Learning Challenges: A Systematic Literature Review

Innovations and advancements in modern technologies have induced changes in every sphere of human activity, including education. Smartphones represent modern, state-of-the-art gadgets which aim at fostering the teaching and learning process of EFL (English as a foreign language) learners. Students may experience and enjoy considerable benefits of these smart devices such as ubiquity, portability, around the clock availability, or numerous technological features. Despite offering overwhelming advantages to language learners, both students and teachers need to take into account challenges they often meet and face. Being in its infancy, this phenomenon appears to be underexplored since majority of studies focus on benefits of mobile learning rather than on challenges. Concentrating on pitfalls, this review article attempts to examine original, peer-reviewed research articles written on smartphone English language learning challenges by reviewing pertinent articles in the two acknowledged databases, Scopus and Web of Science. The research results reveal that the reviewed studies contain identified drawbacks to varying degrees, while approximately one third of articles did not present any challenges. The detected pitfalls, such as smaller dimensions of smartphones, Internet connectivity issues, readiness level of both practitioners and learners, or unbalanced development of the four language skills (listening, reading, writing, speaking), are further addressed and discussed, followed by suggesting the possible solutions to these issues. Finally, it is emphasized that further research needs to be conducted in this regard to shed more light on challenges that both students and practitioners need to tackle.


Introduction
Modern technology has considerably influenced all human activity, including education. Technological advances raise possibilities of improving education and enhancing the teaching and learning process (Rovithis et al., 2019;Straková & Cimermanová, 2018). Mobile technologies along with mobile apps (applications) are becoming an inseparable part of learning (Gangaiamaran & Pasupathi, 2017), and m-learning (mobile learning) appears to offer more in some aspects when compared to CALL (computer-assisted language learning), employing personal, portable devices that offer new ways of learning (Kukulska-Hulme & Shield, 2008;Tarighat & Khodabakhsh, 2016).
It seems that it is the smartphone which has become the center of attention due to several reasons, for example, being superior to standard cellular phones, having computer-like functionality, or because of its increasing popularity and availability (Horvath et al., 2020;Kim et al., 2014). Leis et al. (2015) even proposed a new acronym-SPALL for smartphone assisted language learning as smartphones demonstrate capabilities far beyond standard cellular phones. It is suggested that they can be rather beneficial for the purposes of enhancing the language learning process.
One of the key features of smartphones is the possibility to install third party applications. Mindog (2016) maintains that apps have become popular technological tools which hold considerable potential as regards facilitating language learning. It seems reasonable to assume that one app may not offer a sufficient number of solutions students seek for, which can be resolved by installing a higher amount of smartphone applications, depending on which aspects of language learners wish to focus. "This is the best thing that apps can bring: a portable solution to every learning style which can suit different language learning skill requirements: grammar, vocabulary, reading, listening, writing or speaking" (Rosell-Aguilar, 2014). Other benefits language learners can enjoy involve possibility to practice language items anytime and anywhere, portability, taking tests on different language skills, sharing learners' proficiency with their peers, practicing the fours skills on the same device, having lessons and tips on their apps on different skills, chance to have fun and knowledge together, the fact that aps can be technologically advanced and linguistically benefited at the same time, apps price (some can be free), and possibility to use them 24/7 (Hossain, 2018).
However, adopting new technology for the language learning purposes also presents formidable challenges for both learners and teachers. Lack of attention and concentration, which can be also caused by multitasking, poses a serious problem (Klimova, 2019). In connection with this, Chen and Yan (2016) explain that multitasking can be regarded as a major source of distraction in the realms of academic performance. "Among the downsides are also problems with Internet access and connection, a small screen size, or a lack of face-to-face contact" (Klimova, 2019). Other issues surround English language learning apps. Metruk (2020) explains that because app developers are working 24/7, the number of apps on the market is overwhelming, and it may be rather difficult do choose the appropriate apps. It is also the app functionality which is often questionable as a number of apps contain bugs that need to be dealt with. Heil et al. (2016) maintain that most of the apps appear to be decontextualized, concentrating on individual isolated words than on authentic language production. Finally, it is also both learners and teachers who might not be fully prepared to effectively and appropriately utilize English language learning through smartphone. Implementing smartphones into the teaching and learning process represents the challenge that needs to be addressed and discussed in years to come.
While the majority of articles on smartphone language learning concentrate on effectivity and benefits of smartphone learning, the research on pitfalls and drawbacks still seems to be in its infancy. As new smartphone features and apps are being developed on a daily basis, further investigation into this area ought to be conducted. Therefore, this study attempts to examine original, peer-reviewed articles from 2016 to 2020 in order to cast more light on the challenges as regards the smartphone English language learning in the past 5 years.

Method
This article is based on a systematic review of articles in the databases Scopus and Web of Science (WoS), following the preferred reporting items for systematic reviews, PRISMA (Moher et al., 2009). The search string in the WoS database within the field "Topic" was "smartphone*" AND "English" AND "language" AND "Learning." In the Scopus database, the same search string was employed within the field "Article title, abstract, keywords." The inclusion criteria were as follows: • • period of article publishing was from 1st January 2016 to 31st December 2020; • • only peer-reviewed articles were included; • • the language of articles was English; • • the articles predominantly focused on the use of smartphone within English language learning.
The exclusion criteria, elements which disqualify papers from being a part of the review article, were as follows: • • conference papers and review studies were not considered; • • articles in languages other than English were excluded; • • articles not focusing on smartphone and English language learning were not involved; • • inaccessible articles were (also) excluded.
The search was performed on 19th January 2021, and initially, 195 results were found in the Scopus database and 152 results in the WoS database, which accounts for altogether of 347 articles. After limiting the results to the period of 2016 to 2020, type of article: article, and language: English, 88 Scopus and 75 articles, totaling 163 articles, remained. After removing ineligible (47), inaccessible (18), and duplicate articles (42), 56 articles were selected for the purposes of this study. Figure 1 displays the selection procedure. This article attempts to explore the challenges of using smartphone for English language learning, and for these purposes the following research question was formulated: RQ 1. What are the identified challenges of smartphone English language learning in the reviewed research articles?
The selected articles were examined as regards whether they contain any challenges, drawbacks, or pitfalls within the conducted research related to smartphone English language learning.

Results
A total of 56 articles were selected in this study. Their authors, title, countries involved in the study, objective, and identified challenge(s) are displayed in Appendix 1. Most of the studies were conducted in Saudi Arabia (7), followed by Indonesia (6), China (4), Japan (4), and Taiwan (4). Years in which the articles were published are displayed in Figure 2.   Twenty out of the fifty-six articles, which accounts for 36%, do not contain any smartphone-related challenges. This may be since studies generally concentrate on how effective employing smartphones in the process of teaching and learning English is (focusing on individual language skills and systems), rather than paying attention to pitfalls and downsides. The remainder of articles contained drawbacks that came into being when conducting the given studies to a varying degree.

Smartphone Dimensions and Connectivity Issues
Issues such as small screen size or Internet connection problems represented challenges which were predominantly identified in the articles. The small screen size was reported in altogether eight studies (1,30,31,32,33,48,54), and Internet connection related issues were mentioned in five of them (14,20,29,32,46). Screen size of smartphones is considerably smaller when compared to tablets or computer, which seem to cause problems to EFL learners when practicing particular language skills and systems. Enhancing their language abilities may be, therefore, sometimes annoying, which may not result in improving the given aspects of language. Slow Internet connection and problems with its stability may also hinder the learning process, for instance when speaking skills are practiced by having a conversation with a peer, during which more data is used. However, it appears that Internet providers are constantly working on covering further areas in particular countries, and they are increasing its speed and stability, especially in the age of coronavirus pandemic.

Learner's Disinterest and Unawareness
Some studies also revealed that the research participants' level of interest in (smartphone) apps was rather low (2,17,23,36). Five articles reported that there also exist issues related to using smartphone and smartphone apps for nonlanguage learning purposes (4, 23, 29, 37, 39, 55) despite the learning potential and possibilities of smartphones. It appears that EFL learners tend to use their smartphones for getting information or communication purposes to a greater extent in comparison to working on their language abilities. This may be related to the fact that teachers and learners might be underprepared for the smartphone English language learning since participants' (un)readiness and possessing limited knowledge about available emerging technologies were detected as well (15,38,39). It should be also noted that learners appear to be in need of some guidance when it comes to using smartphones for language learning purposes (23), especially as far as the younger learners are concerned (29). Moreover, they must also realize that they have to be active (27) within its utilization for language learning. Otherwise, the learning process may be hampered.

Underuse of Smartphone Apps
General underuse of apps has also been reported (13, 38), which can be related to the fact that English might not be the predominant language used (7), or that many apps require a good command of English (38). In a similar way, the study performed by Jurkovič (2019) also shows that the interactive/productive activities research participants engage in are predominantly performed in their mother tongue. This is definitely an issue which deserves attention of instructors and researchers in upcoming studies, also due to the fact that the overuse of L1 somehow contradicts the principles of communicative language teaching/learning. One of the solutions to this matter is that apps should take into account the CEFR level of a learner's L2-this would better suit their language abilities and may then result in more effective learning.

Unreadiness of Learners and Teachers
Further, the literature review reveals that both learners and teachers ought to undergo adequate training; for example, learners should be trained how to use various apps such as e-dictionaries (30), or how to use language learning strategies mediated by smartphones (53). It is also the case of teachers who play an important role, as was revealed in five studies (19,29,34,39,56). It seems that both early and novice practitioners as well as more experienced instructors require further preparation before integrating smartphones into the process of English language teaching and learning. Faculties preparing prospective teachers need to rise to this challenge and modify their curricula in order to adequately prepare them for the modern teaching profession.

Unbalanced Development of Language Skills
It is a widespread assumption that the appropriate use of smartphones in language learning environments may facilitate the learning process and enhance learners' language abilities by honing and enhancing their language skills. However, it seems that not all systems and skills are developed equally. For example, in study 13, participants do not think that smartphones help them develop their speaking skills. Further, individual systems and skills are practiced to varying degrees, which demonstrates the unequal distribution of developing the language items. In a similar way, Fatemeh's study (21) (2020) also pinpoints different language skills and the degree of their perception, indicating that not all language skills are equally polished. The students were not as positive for other skills and systems as they were for the reading skill and vocabulary system. The study performed by Jurković (31) (2019) also supports this notion by confirming that there is a preponderance of receptive activities such as reading emails, listening to music, watching video clips, or reading daily news when compared to productive/interactive activities (e.g., writing short messages, communicating with classmates, writing emails). It appears that EFL learners tend to inline more toward the acquisition of receptive skills when compared to practicing, for example, the skills of speaking, which may be the most difficult skills of the four skills (Cahyono, 2016), at the same time being the so-called primary skill (Mishan & Timmis, 2015) or intuitively the most important one (Djigunovic & Krajnovic, 2009).

Other Issues
Several issues arising out of using smartphone and smartphone apps for language learning purposes such as difficulties or inconvenience with using apps, amount of time spent doing particular tasks, distraction while working on their language skills, problems with typing and small screen size, feedback, or interface problems were identified in studies 16,17,29,32,33,35,43,46,47,49,50,54. Finally, some research participants perceived smartphone and their apps in a more negative manner, as expressed by students in articles 36, 43, 45, 48, and 56. Therefore, the perception of smartphone as an English language learning tool was not always positive, and future studies ought to examine and analyze the negative attitudes toward smartphones and smartphone apps in order to rise to these challenges.

Discussion
The objective of this review article was to identify and examine the pitfalls and challenges of smartphone English language learning in studies performed on this matter between 2016 and 2020. Despite the fact that these smart devices offer plenty of opportunity to facilitate and enhance the teaching and learning process, the identified challenges must be taken into account and ultimately overcome and solved. Ubiquity, portability, and availability of smartphones take its toll on small keyboard and display, which has been reported in several studies. The smaller dimensions hinder at times work with smartphones and their apps, and may cause some problems when fulfilling tasks in order to practice their language items. This can be partially resolved by purchasing a smartphone with larger display dimensions, or by developing and installing app that would project a virtual QWERTY keyboard without the necessity of installing it. Nevertheless, seeking solutions to these issues may not be easy and straightforward, and further studies ought to concentrate on these topics.
Slow Internet connection, its availability, and stability is something that could be improved in years to come; Internet providers seem to offer faster and more stable Internet connection to its users from year to year. However, schools and other institutions offering education need ensure that their Internet connection is rather fast and stable so that the learning process can be facilitated by the appropriate use of smartphones and other technology during English classes.
Level of readiness of both teachers and learners, which often seemed to be low, was identified in some studies, representing a major issue as regards using smartphones for teaching and learning English. This could be partially resolved by building the awareness of smartphones and their prospective use in EFL settings. Encouraging, promoting, and increasing the awareness might result in more appropriate and effective utilization of these smart devices in the process of English language learning. Moreover, providing them with some training before using particular apps and tools may also prove beneficial. Finally, learners need to understand that they have to adopt a proactive approach when utilizing modern technology for learning purposes so that the learning process is indeed facilitated.
As far as instructors are concerned, this can be done by directing particular attention to the implementation of modern technologies into the teaching and learning process. Further, more experienced practitioners can attend and undergo adequate training in this regard so that they are more properly prepared for its effective integration into both formal and informal settings. Implementation of new technology to enhance the teaching and learning process is not an easy and straightforward process, which requires time and preparation, and both students and teachers need to understand that their level of preparedness and readiness appears to be mutually dependent-both groups need to take action.
Apps language was also regarded as a pitfall within some studies-students seemed to have overused their mother tongue instead of the target language-English; it should be noted that English language learning apps ought to take into account the language level of app users according to the Common European Framework of Reference for Languages (Council of Europe, 2018). Further, following the principles of communicative language teaching, the use of L1 ought to be limited as much as possible, with a sound use of the mother tongue, especially within instances during which the learning is facilitated (Hanáková & Metruk, 2017).
When it comes to practicing language items using smartphones, the literature review revealed that individual language skills and systems are developed to varying degrees. Instructors ought to guide their learners to more-or-less equal practice of all the language systems and skills. Learners need to understand that they can employ a variety of activities in order to develop (also) their speaking skills and subskills, such as utilizing various Internet chat protocols, using voice recordings, or adopting online software, applications, and platforms for practicing this productive skill. Thus, one of the most critical and, at the same time, challenging skills, the skill of speaking, can be practiced and eventually enhanced.
Finally, learners encountered some problems while doing their language work on their smartphones. Distraction, feedback issues, disproportionateness of level of difficulty within various tasks, or spending too much time on performing the tasks need to be considered by teachers and app developers so that the teaching and learning process is ultimately facilitated.

Conclusion and Recommendation
Undoubtedly, modern technologies offer new ways of improving the learning process of EFL learners, and with new generation of pupils and students (e.g., Generation Z or Generation Alpha), language practitioners need to be aware of technology-mediated instruction in order to facilitate the language learning process. However, careful planning and adequate preparation is necessary so that smartphones are used wisely, effectively, and appropriately in order to foster and enhance students' language learning. This review article has revealed that a number of challenges need to be addressed by teachers when modern technologies are implemented into the teaching and learning process, placing heavy demands on both pre-service and in-service teachers.
The limitations of this paper arise out of the conducted studies, which contain different sampling and sample sizes, various methodological approaches, and various ways of exploring diverse aspects of smartphone English language learning. It can be concluded that numerous issues as regards using smartphone for language learning purposes must be examined, discussed and addressed by practitioners and researchers. In this modern era, with constantly emerging new technologies, third-party apps, and smartphone features, further exploration in this field is absolutely vital, and additional studies in this regard will prove useful and beneficial. Upcoming research exploration ought to also concentrate on the actual implementation of these smart devices into the language classroom, along with types of activities, resources, and applications which instructors take into account when mobile learning is employed. Perhaps concentrating only on a selection of challenges in particular papers, examining them in more detail, and producing new research outcomes may result in possible and viable solutions to these pitfalls. Finally, the conducted studies need to be mutually compared in order to correlate the gathered outcomes, which should result in generating more reliable and relevant information on this matter. Korea "To see how students in two major universities used smartphone apps to informally supplement their foreign language learning" (p. 1036).
Students' preference for using their cell phone. Some participants do not regard learning L2 via mobile apps as interesting.

Cambodia
To investigate "whether digital flashcards may be used to improve grammatical accuracy" (p. 10).
Not mentioned 4 Huzairin et al.

Indonesia
To explore "EFL learners' most frequently-performed EFL learning activities through smartphones, the predominant online language use, and the relationship between EFL learners' predominant online language use and their perceived EFL proficiency" (p. 103). The Internet activities conducted by means of learners' smartphones are not primarily done for learning English 5 Suresh and Sreevani (2020)

India
To analyze "the increasing demand for smartphone users to learn the English language among undergraduate students and identify the language skills that are enhanced after using a smartphone" (p. 2357).
Not mentioned.
Philipines. "To apply the augmented reality (AR) technology in storytelling to enhance and give a more motivating and fun reading experience to children" (p. 3681).
Not mentioned.

Putrawan and Riadi
Indonesia "To investigate EFL learners' predominant language use for their online informal learning of English through smartphones" (p. 695).
Learners' smartphones are not used for the purposes of informal learning to a maximum extent.
8 Machmud and Malik (2020) Indonesia "To investigate and understand high school students' perspectives of using Smartphone use in learning English as a Foreign Language" (p. 4).
Not mentioned 9 Al-Ahdal (2020) Saudi Arabia "To find out how useful the Podcasts are in improving the pronunciation skills of the Saudi EFL learners given the facts that English is a foreign language for them and their exposure to real time native pronunciation of the language items is really limited" (p. 92).
Turkey "To understand the extent to which English as a foreign language learners use technology for their autonomous language learning beyond the classroom" (p. 48).
Not mentioned 11 Seraj et al. (2020) Bangladesh "To explore Bangladeshi tertiary level learners' readiness of using smartphone and problems for learning oral English communication skills" (p. 148).
Not mentioned 12 Akkara et al.

India
To study "the impact of MALL in improving a) speaking skills b) segmental and suprasegmental features of pronunciation and c) the viability of bring your own device (BYOD) approach" (p. 280).
Not mentioned.

Slovakia
To explore "students' perception and attitudes towards the use of smartphones for the purposes of learning and practicing English" (p.

537).
Language learning planning issues. Learners do not believe that learning L2 is dependent on their smartphones.
Underuse of smartphone English language learning applications. Learners do not think that their speaking skills can be improved through smartphones.
There exist varying degrees in terms of practicing language skills -some can be practiced to a greater extent than others.

Malaysia
To examine the "data collected from 560 undergraduates (n = 560) who were immersed and exposed to 360-degree videos and VR experiences for degree level courses on English (as a second language), Mandarin (Chinese) (as a third or foreign language, and Arabic (as a third or foreign language at four public university campuses in Peninsular Malaysia" (p. 373).
Patchy Internet connections. Limited availability of materials which exploit the virtual reality experiences and 360-degree videos within producing the quality content.

Indonesia
The study attempted "to reach four aims: (1) to investigate the implementation of digital literacy in a private junior high school Temanggung; (2) to identify teachers' attitude in practicing digital literacy, (3) to explore the challenges, and (4) how to cope with them" (p. 1508).
Not enough technology source. School inability to afford sufficient technology due to limited funds. Learners' readiness for the purposes of learning technology. 16 Ebadi and Bashir (2021)

Iran
To investigate "the impact of mobile-based dynamic assessment (MDA) on EFL learners' writing skills" (p. 1).
Conducting the missions was time-consuming at times for the experimental group.
Inability to see and hear the instructor as well as learners' preference to provide responses verbally represented challenges for the experimental group.
Finding the erroneous passages was thought to be difficult in the V group (group that received the voice-based mediation). Students were somehow stressed during the verbal responses. Further, delivering voice to the teacher can be regarded as another problem for the V group It was not easy to handle the lengthy voice files for the V group as they were more in favor of the short voice files.
17 Ishaq et al. (2020) Pakistan "To look at teachers, government officials, and students for Literacy & Numeracy Drive (LND), a smartphone app for students in Punjab province, Pakistan, to teach languages and math" (p. 86).
Not an easy-to-use interface It was not easy to find the app icon. Poor interface design, font and color issues, and no assistance with difficulties resulted in the fact that most respondents were not interested in using the app. Inconsistency of the app with the school syllabus. Stakeholders' feedback was not sufficient.

Russia
To describe "methods of research and determine the level of effectiveness of electronic applications using Quizlet as an auxiliary element in teaching English" (p. 148).
Not mentioned.
19 Barrett et al. (2020) Taiwan "The main goal of this article is to understand English undergraduate oral presentation needs for mobile seamless learning in order to develop a mobile learning environment and enhance students' oral presentation ability" (p. 1).
Instructors are in need for training with technology.

20
Al-Mubireek (2020) Saudi Arabia "To investigate the effectiveness of using handheld devices such as smartphones and tablets for language teaching purposes" (p. 204).
Mixed feelings of teachers. Some problems were identified, For example, monitoring students' use, imposing discipline, issues with connection and technical support, technology misuse.

21
Nami (2020) Iran "To explore the type of language learning apps commonly used by 381 university students at Amirkabir University of Technology and their perception towards the effectiveness of these apps for developing learning language skills" (p. 82).
Students were more positive for vocabulary and reading than for other language skills. Students think that not all language skills can be equally practiced and developed during the use of educational apps. To "propose a method that enables L2 learners to study new vocabulary items during their dead time, such as when commuting to school or work" (p. 135).
Not mentioned.

23
Lyrigkou (2019) Greece To investigate "76 Greek adolescent learners of English between the ages of 13 and 16, and used a speaking test, a questionnaire and a semistructured interview to examine participants': speaking performance, frequency of interaction with English through a range of media, and their agency and exerted effort during informal contact with the language" (p. 1).
Some incidental gains are acknowledged by the learners; however, they seem to be sporadic and inconsistent so as to considerably contribute towards language achievement.
An individual ought to be guided in order to exploit the learning potential of informal learning sources.
Not mentioned.

Taiwan
To explore "the effects of 40 participants' perceived ease of use, usability, usefulness, learner attitude, satisfaction with the use of GBELA, and self-efficacy in smartphone and GBELA usage" (p. 359).
Not mentioned.
Poland and Croatia "To examine the role of online language use through smartphones among students of various disciplines and its possible effects on enhancement of their foreign language skills" (p. 173).
Not mentioned.

27
Klimova (2019) Czech Republic "To illustrate that foreign language learning supported by a personalized smartphone app can be effective in the enhancement of university students' performance by implementing smartphone app learning in a continuous assessment" (p. 1).
Learners need to understand that they have to be active within their learning -the teacher encouraged the learners continuously via posted notifications so that they use the mobile app and work on their vocabulary outside the classroom.
28 Alzubi et al. (2019) Saudi Arabia To investigate "the impact of reading learning strategies (RLS) mediated by smartphone features and applications on the learners' psychological autonomy in English as a foreign language (EFL) reading context among undergraduates in Saudi Arabia" (p. 99).
Not mentioned.

29
Nguyen and Yukawa (2019) Vietnam "To examine the possibility of Kahoot application and suggest feasible implications for teachers, learners, and the school teaching curriculum" (p. 289).
Technical problems such as Internet connection. Potential competitiveness of learners.
Early teachers require further training, also because of different levels of ages.
Young learners have to be controlled so as not to lose concentration on studying.
China "To explore types of motivation for smartphone dictionary use among Chinese university EFL learners" (p. 68).
Smartphone dictionary apps need to be customized appropriately.
Small screen size of smartphones. Chinese learners of English need to undergo training how to use e-dictionaries.
Pedagogical encouragement for the so-called self-initiated dictionary usage is not sufficient. Female learners might need more instruction how accessing new e-dictionary applications when compared to the males. Low-proficiency learners could be most interested in getting guidance on decoding entry information.
Lack of training in dictionary use. Slovenia "To investigate the main online informal activities that undergraduate students in Slovenia perform through their smartphones, and the relationship between their involvement in online informal activities in English and their perceived communicative competence in English" (p. 28).
Learners are more active within online receptive rather than productive activities.
The productive activities that are involved concern writing short text messages, communicating with their peers as regards study-related matters, and composing emails. The majority of participants, however, perform these tasks using their L1.
Just few learners are involved in MALL activities on a regular basis. Affordances enabling the utilization of English in authentic contexts are used to a lesser degree than one would expect. Small screen size.
32 Khan et al. (2019) Saudi Arabia "To explore the potential usage of M-Learning in English for specific purpose (ESP) classes" (p. 60).
Limited free access to Wi-Fi in the classroom poses a problem within the learning process. Glitchy battery issues. Small screen results in typing problems. Download time.

33
Jon and Yunus Malaysia "To investigate pre-university students' perceptions on the use of mobile learning (e.g., learning via smartphone, iPad, tablet computer and Personal Digital Assistant) for writing" (p. 1481).
Only 77.7% of the learners expressed agreement that the utilization of m-learning contributes towards developing their MUET (Malaysian University English Test) writing.
One respondent made the following comment: "Sometimes, it's difficult to draft my writing using mobile device because the screen is smaller than the computer's screen. Besides, I don't feel comfortable reading academic journals or long information using mobile because it's hard to read it" (p. 1489).
Saudi Arabia To investigate "teachers' perceptions and the current actual practices of utilizing a package of three categories of smartphone applications as a prescribed teaching technique with the purpose of fostering Saudi tertiary students' oral skills, correlating these perceptions with actual classroom practices" (p. 74).
Teachers are concluded to have high inspiring perceptions of utilizing smartphone applications for promoting Saudi tertiary students' speaking skills. Nevertheless, their actual practices were inferior to these perceptions. Classroom practices reveal weaknesses in terms of using smartphone applications in language classrooms.
Teachers tend to struggle with several factors that make this kind of classroom practices weaker. "Consequently, the study recommends stakeholders to design speaking lessons with the aid of smartphone applications, allow flexibility in syllabi for speaking activities, and encourage teachers to apply such applications effectively" (p. 89).

Russia
To present the "research results on mobile learning of English for specific purposes to ecology students with the help of the Quizlet learning platform" (p. 920).
1 out of 10 respondents regarded the need to sing up as a problem. Limited charge of the device was also deemed as an inconvenience as regards the use of a mobile app.
To analyze "the learning needs for developing ESP knowledge and skills through the use of smartphones and QR codes" (p. 124).
The positive attitudes were not displayed by the expert group. Language for specific purposes instructors maintained that not everyone owned a smartphone, possibly due to limited funds, which would result in unfair education. Both e-learning and u-learning (ubiquitous learning) approaches were recommended by the interview teachers so that each student could access the materials, not being limited by smartphone ownership. Bosnia and Herzegovina To explore "the use of digital technology for educational purposes" (p. 275). It appears worrying that the respondents "should still not fully understand that digital technology can be utilized in education to great effect and their teachers' unreserved approval" (p. 287).
38 Luef et al. (2019) Korea To examine "whether the use of smartphone apps for language learning was influenced by linguistic proficiency of the learners and, further, whether proficiency levels in different first and second foreign languages showed some interaction concerning the learners' propensity for app use" (p. 34).
Apps underuse. A good command in English is required by many apps. Methodological issues.

Indonesia
To investigate students' "own use of android applications to help them in learning English. Specifically, it investigated the types of apps the students use, examined their motives in using the apps, and figured out how the apps were perceived to help in acquiring English" (p. 95).
Students' limited awareness of technologies which demonstrate potential to facilitate their English language learning. Teachers' negative responses for using app in the classroom; the instructors perceived it to be ineffective in terms of learning English.
40 Yurdagül and Öz (2018) Turkey "to investigate the attitude of students in higher education towards smart phone use in the context of foreign language learning" (p. 1).
Not mentioned.

41
Alzubi and Singh Saudi Arabia To examine "the impact of social strategies mediated by smartphone features and applications on socio-cultural autonomy in English as a Foreign Language (EFL) reading context among undergraduates in Saudi Arabia" (p. 31).
Not mentioned 42 Doan (2018) Vietnam. "To identify factors that drive students' intention to use smartphones for language learning based on the Technology Acceptance Model by Fred Davis (1989)" (p. 47).
Not mentioned.

43
Ludwig (2018) Germany To examine "the impact of a mobile vocabulary learning app on secondary school students' vocabulary performance, also giving some indications about the students' development of foreign language learner autonomy" (p. 306).
The log-in process. Learners did not fully trust the application, or they were not used to this method of learning lexis.
The app was regarded as an additional tool (rather than a learning tool), monitoring the paper-based self-study progress.
Apps were excluded by some students as a tool for learning vocabulary. Students' distraction by incoming messages and notifications.
Most of the learners claimed that their vocabulary learning was not positively affected by the app and that their lexis test results were not influenced by the app learning.
United Arab Emirates "To survey student opinions about technology in order to best implement and utilize technology in the classroom. (p. 309)" Students preferred more books and paper in comparison to laptops (the difference in preference was not big).
The participants may seem to believe that books and paper facilitate the notetaking to a higher extend, and that there are fewer distractions when the books and paper are involved.

46
Lee (2017) South Corea To examine the "South Korean university students' views of the advantages and disadvantages of three popular smartphone apps, Memrise, Duolingo, and Busuu, which aim to improve language proficiency" (p. 984). Too much seem to have focused on vocabulary and the lexis they learned was not utilized in a practical manner. Some more interesting and fun work ought to be implemented in order to motivate the students. Some learners regarded activities as easy, other as appropriate or too difficult. Lack of social interaction. Some issues with memory, data, Wi-Fi access, and battery life.
No. Some themes encouraged or discouraged the participants in terms of using lexis from the academic world list. While one concrete theme seemed to have afforded learners more opportunities, others appeared to have a limited impact.

Author
48 Chou et al. (2017) Taiwan To explore "the effects of the BYOD (bring your own device) approach on student language learning" (p. 63).
Learners showed uncertainty as regards the ultimate efficacy of bring your own device (BYOD) approach. Some extra effort was needed for the preparation for the BYOD test.
There was some dissatisfaction with the application features and phone hardware among some female learners.
Small screen size.
49 Sung and Poole (2017) China To investigate the "college students' use of a popular smartphone social networking application, WeChat, in a tandem language learning project" (p. 97).
The difficulty of making time for an out of class project and that it was "easy to forget/ overlook when things get busy. Some difficulties with expressing oneself. One participant maintained that "it can be hard to express the right emotions as with any messaging program" (p. 109).
Some difficulties with finding topics for discussion. One of the participants suggested that "because the WeChat partners had no interaction in real-life, there was [sic] not many common topics to discuss. Sometimes when communicating, there was nothing to talk about" (p. 109).

50
Freiermuth (2017) Japan To study the use of smartphone technology and downloaded application in a flipped English class.
The amount of time dedicated to making the videos.
51 Hsieh et al. (2017) Taiwan. "To explore the benefits of the flipped classroom model for learners of English as a Foreign Language" (p. 1).
Not mentioned.

52
Ngadiran and Alias Malaysia "To examine tertiary students' current ownership and usage patterns of mobile devices particularly in learning, their expectations in the use of M-learning technology in future learning, as well as their perceptions in employing mobile language learning" (p. 259).
Not mentioned.
53 Alzubi and Singh (2017) Saudi Arabia To explore "the improvement of LA through the explicit use of LLS in EFL reading in a mobile-assisted language learning (MALL) environment among English as a foreign language (EFL) readers enrolled in Preparatory Year program at Najran University in Saudi Arabia" (p.

59).
Students expressed the need for undergoing training on learning strategies as regards smartphone learning.
The research results further suggest that mild utilization of language learning strategies can negatively influence the learners' autonomy.

54
Vurdien (2017) Spain To investigate "how a group of advanced-level EFL students read articles on their smartphone to acquire new vocabulary which they later inserted in their essays on wikis" (p. 1).

Small screen size.
Inability to open other windows on Google in order to check the meaning of some vocabulary. Feedback was not always perceived as effective. Feedback of a more explicit nature would have been more appropriate. Low concern for errors as regards the feedback.

55
Mindog (2016) Japan To investigate "the utilization of smartphone apps by four Japanese university students to support learning English as a Foreign Language (EFL)" (p. 3).
The reason for using apps predominantly lie in communicating, getting information, and enjoying entertainment rather than in using the apps for language learning purposes.
Language learning seemed to be secondary to other activities.
56 Zhang (2016) China "To evaluate the benefits of mobile APP, English Fun Dubbing, an APP designed for its users to practice oral English, in the field of pedagogy" (p. 4).
Only one fifth of the respondents agreed that EFD (English Fun Dubbing) app "was good for group discussions" (p. 8).
Motivating and inspiring leaners who might feel indifferent about actively participating in the app-aided learning merits further investigation as three students submitted less than eight dubbings.