1. Introduction
Technology, especially mobile technology, has played an essential role in students’ learning process during the COVID-19 pandemic. According to technologists, mobile learning involves learning on a mobile device (e.g., tablet, mobile phone, laptop) [
1]. Additionally, mobile learning is considered a continuation of e-learning. In learner-centred theory, it is believed that mobile technologies allow students to learn in a constantly changing and nondeterministic environment to maximise learning opportunities [
2]. As part of school education, mobile learning has changed in several ways: (1) the way teaching content is presented; (2) how students learn; (3) the methods teachers use to teach; and (4) the way students interact with teachers [
3]. Mobile learning has established itself as a common phenomenon in educational pedagogy that has received widespread attention from educators and researchers.
Mobile learning research originated at the end of the 20th century. Researchers have extensively studied this field over the past two decades, providing insights into theory and practice. After many researchers have studied mobile learning from various perspectives, some researchers pointed out the need to review the literature in this field. One good example is Wu et al. [
4], who conducted a meta-analysis of 164 mobile learning studies from 2003 to 2010. Their results showed that mobile learning effectiveness and system design are primary research areas, with system design having dominated the research trajectory. Besides meta-analysis, bibliometric analysis is also a common method to study this field’s literature. For example, Khan and Gupta [
5] conducted a bibliometric analysis of mobile learning research from a student-centred perspective. According to co-citation analysis of 722 articles, four clusters (concept, application in education, designing framework for model learning/acceptance, and emerging technologies) of hotspots were identified. In a similar vein, Goksu [
6] analysed 5167 mobile learning articles published until September 2019. The study uncovered mobile learning research trends. They found the researchers coming from Taiwan, USA, Mainland China, and England were the most productive with Taiwan responsible for the lion’s share of research produced. In addition, the single university producing the most research in this area was also in Taiwan. Lastly, keyword co-occurrence analysis showed mobile devices, higher education, mobile technologies, tablet, and smartphone as high frequency keywords in this field.
Due to its high functionality, CiteSpace has been the go-to software of bibliometric analysis conducted by Chinese scholars [
7,
8,
9] but has been utilized less by mobile learning scholars outside Greater China (e.g., Khan and Gupta [
5]; Goksu [
6]). Zhang [
10], as an example, focused on research topics and development trends of mobile learning published from 2010 to 2020 by using three software programs, namely UCINET, SPSS and CiteSpace. The results showed a steady rise in the number of relevant research papers as well as several highly cited and influential publications. The uncovered research themes included technical support, learning design, learning mode and practice. In addition to research published in Chinese journals conducted by Chinese scholars, Xu et al. [
11] carried out an analysis of 2392 papers in the field of mobile learning retrieved from the Web of Science database from 1997 to 2017. That study showed mobile learning research has received extensive attention from researchers in various research fields around the world, involving three research hotspots, namely the impact of information technology development on mobile learning, the design of mobile learning systems, and context awareness for mobile learning. This study also brought to attention three relevant research frontiers: the application of emerging technologies, the smartphone-based model, and the effectiveness on students’ learning.
While these studies were insightful, CiteSpace software has seldom been used by researchers outside Greater China to explore the field of mobile learning. A broad literature search uncovered only two researchers outside Greater China using this software. Khodabandelou et al. [
12] conducted a comprehensive analysis of mobile learning in the domain of English learning in the 21st century and found research on English mobile learning is growing rapidly and steadily, especially studies on various device-based technologies and applications. Rawat and Sood [
13] performed knowledge mapping of computer applications in education that found mobile learning has received increasing attention in applied information and communication technology in higher education, especially in engineering education. As exemplified by these two studies, CiteSpace software can detect and visualise trends/patterns in published literature [
14].
The existing mobile learning bibliometric reviews have the following research limitations: (1) some of the latest reviews on mobile learning are limited to a single subject (i.e., English); (2) the data sources are extensive but may not be able to summarise the research published in competitive outlets; and (3) the time range of the literature analysed was limited, which cannot fully reflect the overall trend of the research hotspots in this field. Moreover, online learning during the COVID-19 pandemic made mobile learning a common practice, potentially leading to new developments. This study aimed to provide a detailed exploration of the past two decades of publications focusing on mobile learning appearing in the exclusive and competitive SSCI database. The study also aimed to summarise the most influential countries/regions, researchers, and publications. Having access to this information allows for tracing of the origin of this field and to assist scholars in understanding its evolution and future trajectory.
The research questions that guided this study are:
- (1)
What are the mobile teaching and learning publishing trends?
- (2)
Who are the prolific authors in the field of mobile teaching and learning, and how strong are the researchers’ collaborations?
- (3)
Which institutions have led to the development of mobile teaching and learning research and which institutions have had the most extensive collaborations?
- (4)
Which countries/regions have led to the development of mobile teaching and learning research and which countries/regions have had the most extensive collaborations?
- (5)
What are the mobile teaching and learning research hotspots and what future trends can be predicted?
4. Conclusions
The aim of this study was to uncover: (1) the mobile teaching and learning publishing trends; (2) the prolific authors publishing and collaborating in publications on mobile teaching and learning; (3) the prolific institutions and their collaborators publishing on mobile teaching and learning; (4) the countries/regions producing and collaborating on mobile teaching and learning research; and (5) the predicted mobile learning and teaching research hotspots and trends. Within the time frame examined, a noticeable increase in mobile teaching and learning articles started in 2008 and peaked in 2021. While research on mobile learning and teaching was found to have been produced throughout the world, the lion’s share is from Taiwan. Notably, Gwo-Jen Hwang, along with other Taiwanese researchers, has paid substantial attention to this field. There is a noticeable collaboration between the authors that are producing most of the research in this field, with more research production resulting in more collaboration. This can be shown for not only individual authors but also countries/regions and for institutions. Keyword co-occurrence analysis and cluster analysis found 11 relevant clusters that could be narrowed down into three mobile learning and teaching hot topics. The most frequent keywords include: student, higher education, adoption, game, achievement, and intention. The most frequently cited publications dealt with the effectiveness of mobile devices for learning.
These findings provide scholars with an accessible summary of: (1) the current trends in mobile learning; (2) the active researchers in this field; and (3) the outlets that are most relevant for research produced on this topic. These findings have direct implications for the education and private sectors because mobile devices are not widely adopted in classroom settings and are often considered a learning tool more suited for out-of-class assignments or practice. Summarising the development of mobile learning, especially the effectiveness of mobile devices, allows for an understanding of the advantages and disadvantages of mobile devices for learning and instruction. Once the integration of mobile technology is actively initiated in the classroom by information technology educators, those in the technology industry should aim to develop mobile devices and relevant educational applications/software that can be utilised not only within the confines of the classroom but also to bridge in-class and out-of-class learning.
The findings of this study should be considered in connection with its limitations. First, the results are limited in that search terms for only SSCI-indexed journals were covered. If non-SSCI-indexed journals had also been included or other databases, the results would have differed. Second, the time span of analysis ended in 2021, which some might argue was still in the middle of the COVID-19 pandemic. It would be worthwhile for future research to compare these results before the pandemic to those after the pandemic.