The type of activities focusing on vocabulary learning via mobile phone differs from one research project to another, depending on the level of language proficiency of the learners. Sending e-mail or SMS to students is a common way of learning new vocabulary based on the lessons covered in the classroom. In a study Kennedy and Levy gave the learners the option to receive messages covering known words in new contexts through SMS to their mobile phones amounting nine or ten messages per week. The results indicated that the messages were very helpful for learning vocabulary .
Similarly, Thornton and Hiuser sent short mini-lessons for learning vocabulary through e- mail to mobile phones of the students three times a day. They used new words in multiple contexts for the learners to infer the meaning. The results showed an improved range of scores on post-tests which were very encouraging .
There are other strategies for learning vocabulary via mobile phones. Learners can be provided with some tailored vocabulary practices based on activities performed in the classroom. They are, then, asked to complete them on their mobile phones and send them back to their instructors.
Learning vocabulary can also be accompanied by the pictorial annotation shown on learners' mobile devices for better understanding of new words. In a study conducted by Chen, et al., learners were provided with verbal as well as pictorial annotation for learning English vocabulary. Results of a post-test showed that the pictorial annotation assisted learners with lower verbal and higher visual ability to retain vocabulary .
Listening exercises may be considered the first stage in learning a second language. With the advent of the second generation of mobile phones, it is now possible to design a mobile multimedia system for learning listening skills through listening exercises.Huang and Sun designed a system composing of two subsystems. A multimedia materials website that uploaded and maintained video materials, and a set of multimedia English listening exercise on the mobile phone for the learners to repeat exercises in English listening in a ubiquitous learning environment. They attempted to implement the mobile multimedia English listening practice system based on capabilities of the mobile technology providing learners download multimedia sound contents from mobile devices, register the learning website, order mobile learning courses and activate reception of learning courses. According to Huang and Sun, mobile multimedia English listening exercise system can enhance learner's English listening abilities to a high degree . It is also possible to design a platform in which learners listen to a text by vocal service on their mobile phones, followed by a listening comprehension quiz based on the text.
Grammatical points can be learnt through a specifically designed program installed on mobile devices, in which grammatical rules are taught, followed by multiple-choice activities where learners select the correct answer from the given alternatives. Grammatical exercises can be in the form of 'true-false' or 'fill-in the blanks' which are to be responded by the learners. Grammatical explanations may also be presented to learners via vocal service or short message service.
The second generation of mobile devices enable their users to access multimedia functions including listening and speaking ones. A good m-learning service should consist of speech facilities for transmitting voice. Having such facilities, the learners may download dictionaries on the PDA1 with sound functions so that they can learn the correct pronunciation of unfamiliar or new words to be able to fulfill their learning needs. Mobile devices with multimedia function give the learners the opportunity to record their own voice. Then, teachers are able to make a better assessment of the students' weaknesses in pronunciation. This way, by enhancing various functions of the system like providing a dictionary for looking up unfamiliar words and their correct phonetic form, the pronunciation as well as speaking skills of the learners can be well improved.
The Praxis learning podcast line is a platform providing a context-driven, social-based, and software-enhanced website for learning foreign languages. It has recently been working to release mobile language learning features for PDAs, smart phones, etc., enabling learners to learn phonetics of a given language in an interaction way using multimedia functions on the mobile phones (Microsoft research program).
The speech aspect of mobile learning is as significant as textual aspect of it, since it enables learners to comfortably speak with a system recording their voice and allowing them to listen back to themselves. Then, they can compare their voice with an ideal pronunciation and make an improvement in this skill .