In recent years, blended learning (BL) has become popular in educational environment. As it combines traditional and online learning modes, the promise of BL rests on the strengths of both learning approaches. Having this in consideration, the most important aim of the BL design is to find an effective combination of different learning methods which can motivate students to participate inside and outside of the classroom environment (Neumeier, 2005; Senffner and Kepler, 2015). Senffner and Kepler (2015) pointed out that BL is flexible, scalable, and meaningful way of learning since its online component allows students to learn anytime and anywhere without being limited to groups or partners. Regarding this, the mobile technology appears to be an appropriate approach to education since smartphones and other portable Wi-Fi gadgets are related to both traditional and innovative ways of learning and are well aligned with strategic educational goals (Kukulska-Hulme, 2009). Klímová (2017) argued that characteristics such as portability, individuality, unobtrusiveness, availability, adaptability, persistence, usefulness, and usability make mobile devices an ideal language-learning tool. Moreover, the ownership of smartphones among students has grown fast which led to a great popularity of the mobile technology in education, including English as Foreign Language (EFL) learning. Mobile devices have been adapted in the traditional classroom environment and are increasingly used by English language learners (Nasab and Taki, 2016).

Since vocabulary acquisition is considered to be an essential part of language learning, vocabulary mobile learning applications (apps) have become a popular form of mobile-assisted language learning (MALL) (Klímová, 2019). Research has shown that a mobile application designed and based on students’ needs and continuously facilitated by a teacher is effective in the enhancement of students’ performance and contributes to positive learning outcomes (Mahdi, 2017; Rezaei et al., 2013; Klímová, 2019). Despite an increasing number of mobile learning applications offering a powerful learning environment, it is certain that the traditional methods of learning foreign languages are still useful. However, they need to be updated and combined with new trends in education (Mikulecký, 2019). Before the onset of coronavirus, in Slovakia, teaching and learning had been mainly based on the traditional face-to-face learning approach. The technology-based learning tools were implemented only in the case when teachers were willing to do so. After the spread of coronavirus, the traditional learning was disrupted and sudden lockdown forced teachers and students to adapt their teaching and learning. New circumstances made educational institution recognize the importance of technology-based learning tools since they appear to be effective tools for ensuring students’ education. This is especially true for mobile devices. Considering the importance of mobile technology, the present study investigated a mobile learning application called Angličtina Today [English Today] and its usefulness in the process of vocabulary acquisition in the EFL setting of Slovakia. The following research questions guided this research:

It is commonly thought that vocabulary lies in the center of language learning since it is impossible to convey information without having knowledge of vocabulary (Wilkins, 1972; Nation, 2001; Zhang, 2011; Alquahtani, 2015; Gürkan, 2018). In order to increase vocabulary size, both incidental and instructional vocabulary acquisition are required. Incidental learning has been portrayed as implicit since knowledge is acquired independently of conscious attempts to learn. In other words, incidental learning is taken as it is learning without intent to learn (Nation, 2001; Eraut, 2004). According to Schmitt (2010), only ten encounters with vocabulary can lead to its sizeable gain since the repetition affects incidental vocabulary learning. According to his findings, learners who encounter an unknown word more times in informative contexts are able to demonstrate significantly larger gains in vocabulary knowledge than learners who have fewer encounters with a new word. This is in line with Soleimani et al. (2022) whose study revealed that repeated exposure to vocabulary leads to significant EFL vocabulary gains. Despite of this, there is an unknown boundary between word which has been recognized and the word which has been fully understood and learnt in the process of incidental vocabulary learning. Therefore, there is a need of some systematic approach, to ensure vocabulary acquisition which can be reached by intentional learning (Björgvinsson, 2012). It is in accordance with Zhang and Teng (2012) whose study pronounced a significant role of intentional learning. Students need to get input in forms of explanation and clear instructions and they need to practice the language they have learnt which could possibly lead to a successful output (Birkner, 2016). The role of input, information processing, and output has been gradually acknowledged in second language learning. Zhang (2009) believed that these are essential elements in foreign language acquisition, including vocabulary acquisition. Different phases of vocabulary learning can take place in different environments such as traditional school learning environment or technology-based learning environment. Combination of educational technology with traditional methods can lead to effective vocabulary acquisition and thus to achievement of balance in the learning process (Mahdi, 2017).

Poláková (2019) recommended the combination of online interaction with traditional classroom methods. She assumed that blended learning can make learning process more interesting and motivational. Moreover, the previous studies reported positive attitudes of the students toward the use of the mobile application in learning vocabulary which is in accordance with the findings of the study conducted by Lu (2008) who found out that the positive attitudes toward learning vocabulary via mobile phone might be influenced by its characteristics such as portability, immediacy, novelty, and legibility. With regard to the previous statement, Prensky (2005) claimed that when conducting the research regularly delivered information via mobile phone was manageable while the traditional manner of learning failed to arouse students’ interest in study. In other words, using mobile devices as learning tools leads to enhancement of learners’ motivation. The learning materials delivered by mobile devices are more appealing to students, which is not the case with paper-based learning materials. (Gürkan 2018), Butarbutar (2020), and Kohnke (2020) also emphasized that using mobile apps increases students’ motivation since it is more enjoyable in comparison with the traditional methods of learning. The motivation level of the participants seemed to be an important aspect of the study conducted by Ekinci (2017) since, according to him, most of the participants consider BL as motivating and entertaining because it is considered a new method of learning. This is in line with Viberg and Grönlund (2013) who found out that the perceptions of the mobile application users are extremely positive and their motivational level is high toward mobile learning.

Another benefit of using the mobile apps in the process of vocabulary acquisition is the corrective and immediate feedback. This found concordance with Liu (2008), Klímová (2019), and Klímová and Poláková (2020). The research participants of their studies claimed that feedback helps them to learn new vocabulary items and understand their meaning which helps them to improve their language skills. The other factors affecting the learning process are the ease of use and the ubiquitous character of mobile phones. They are portable devices and can be operated anywhere and anytime with no difficulties. These factors have a stimulating effect on the students and their willingness to continue using the mobile app. These findings were supported by different studies (Gafni, 2008; Ekinci, 2017; Gafni et al., 2017; Klímová and Poláková, 2020).

However, the aim of the current study is to discover the impact of the vocabulary mobile learning application on students’ range of vocabulary and to understand the students’ views on the usefulness of the vocabulary mobile learning application in the process of language learning. To the best knowledge of the researchers, no study to date has investigated the overall perception of the students of the mobile applications as learning tools in EFL context in Slovakia. In order to shed more light on this subject, the authors of this study found it an opportunity to conduct research on vocabulary acquisition through the use of BL, including mobile technology, in order to discover the impact of the vocabulary mobile learning application on students’ range of vocabulary, to define the usefulness of the application, and to understand students’ views on the usefulness of the mobile technology in the process of language acquisition.

The aim of this study was to obtain information on the usefulness of the mobile application. On the basis of the research analyses, it may be stated that the results obtained from the quasi-experiment, questionnaire, minute papers, and virtual focus group have been in agreement. There were many results to comment on, but those which could be mutually compared were specifically m-learners’ performance, m-learners’ satisfaction, m-learners’ motivation, content quality, and ease of mobile application use. The comparison and the interpretation of the research results are provided below.

The aim of the current research was to explore the usefulness of the mobile application defined by an improved language proficiency and also general overall satisfaction of the users with the app. The results from this study offer some key findings:

First, the questionnaire, minute papers, and virtual focus group revealed the following positive perceptions of the mobile application users:

These findings accord with those of Gafni et al. (2017) which revealed that using vocabulary mobile learning application has a stimulating effect on the process of learning and contributes to the willingness to continue using the application and to recommend it to others. These findings also support those of Kacetl and Klímová (2019) who indicated that the key benefits of MALL are the enhancement of the learner’s cognitive capacity, the learner’s motivation to study in both formal and informal settings, the learner’s autonomy and confidence, as well as the promotion of personalized learning, and helping low-achieving students to reach their study goals. These findings also re-echo Nuareni’s (2020) claim that the majority of the students has positive perception on the usage of MALL in learning English language. These findings are also in line with the most recent study by Jeong (2022), who claim that MALL helped his students with access to learning contents, created flexible and self-directed learning environment, better interaction, and improved self-efficacy in English learning performance.

Second, the implementation of the vocabulary mobile learning application was effective because the students from the experimental group reached better results than the students from the control group. Moreover, an enhancement of the language skills was also perceived by the mobile application users. This is in line with the results of several other studies that implemented MALL in the process of education when conducting research. For instance, Alqahtani and Mohhamad (2015) claimed that using the mobile learning application enhanced students’ performance as well as their satisfaction. Similar results were found by Lu (2008)who stated that the participants from the experimental group identified more vocabulary than the group learning vocabulary through the printed materials. The same findings were revealed by Palalas (2011) and Gharehblagh and Nasri (2020) who indicated that MALL helped to improve the vocabulary knowledge of EFL students.

Overall, the results obtained from the different quantitative and qualitative research methods proved a high level of the mobile application usefulness. This claim is based on the fact that using mobile application in the process of education helped students to reach better results in the post-test, helped to improve students’ vocabulary and the ability to express themselves more fluently, proved to be user-friendly, and enhanced students’ motivation to learn. Nevertheless, as Klimova (2021) states, teachers have to guide their students in the use of such an app to make the learning process effective and meaningful.

This study helps to understand the perceived advantages and disadvantages of using vocabulary mobile learning application in blended foreign language learning. It turned out that most of the participants found the mobile application beneficial additional learning tool since it helped them to improve their language skills and made learning more fun and less stressful. The obtained research findings can help foreign language teachers to understand the benefits of combining mobile learning with traditional face-to-face learning. It can motivate them to innovate their teaching and lose the fear of using technology due to its seemingly disruptive nature. Furthermore, it might motivate foreign language students to use their mobile devices as the learning tool. Moreover, the findings can assist developers of vocabulary mobile learning applications since students’ preferences are provided in the present study.

In view of the results of this study, some pedagogical recommendations are suggested to EFL instructors. Teachers should be the role models for their students and teach them how to use mobile phones in the process of language learning. Despite the fact that students use their mobile phones on a daily basis, they might not know how to use them as learning tools. Therefore, they need the guidance of a teacher.

It is sufficient for MALL to be implemented only in one of the learning phases, preferably during the information processing phase. Students can be introduced new vocabulary in the classroom environment through the traditional methods of learning and, subsequently, the new vocabulary can be revised through a mobile application, outside the school environment. The last phase of output should take place in the classroom, where the various activities can be used to verify students’ vocabulary knowledge.

When revealing the mobile lessons, it is important to provide learning materials that are in concordance with the curriculum taught in the classroom. The information provided should be well organized, readable, and easy to absorb.

It is not necessary to provide a large amount of vocabulary in each mobile lesson. However, it is recommended to add new vocabulary regularly, preferably after each face-to-face lesson.

Teachers should regularly send notifications and remind their students of new material or testing. If mobile application notifications do not work, it is necessary to look for new solutions to inform students about these events.

It is important to carry out a formative assessment, which makes it possible to monitor students’ progress. The results obtained from the assessment can help teachers to understand the needs of the students and possibly change the learning plans. Formative assessment can also be a motivation for students to use the mobile application; moreover, students are provided with feedback on their learning performance.

It is essential for teachers to ask for feedback from the students and understand their perception of the use of new technologies in the learning process. It can help teachers to improve their teaching and, what is more, students value being asked for their opinion since they feel being recognized when they are given space to express their views. Such an approach can help teachers to create a positive school climate and thus improve the learning process.

It is recommended to give students a free choice and let them decide whether they want to use the mobile technologies in the process of learning or prefer traditional learning through textbooks. Forcing students to use the mobile technologies could provoke resistance to learning. Students must not be punished for their decisions.

Furthermore, it would be suitable to raise other teachers’ awareness of the implementation of the mobile technologies in the process of the language learning which can help students to improve their language skills. The older generation of teachers often resist the use of innovative trends, but nowadays, the implementation of the technology in education seems to be essential. The COVID-19 pandemic clarified the importance of the technologies as traditional learning suddenly switched into distance learning. This could not have worked without the inclusion of the technology in the process of learning.

Naturally, there are certain limitations to be considered in this study. To start with, the research sample size was small; therefore, it was difficult to get more statistically significant results and generalize the study. Additionally, the time the secondary school students experienced the mobile application was relatively short. A longer period may have provided an additional and deeper insight. Furthermore, there was no space to examine the vocabulary retention perceived by the students in the follow-up period. However, this fact was confirmed by different studies whose results were in line with the findings of the present research.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.

The paper is supported by the project Excellence (2202/2022) at the Faculty of Informatics and Management, University of Hradec Králové, Czechia.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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