I attended a number of presentations on mobile technologies in language learning at WorldCALL 2013.
Overall gist I get is that mobile phones are not treated by students as just another distribution channel (but teachers and administration tends much more to see them that way). Students use mobile more for push-based interactions (updates) and short, user-directed, non mandatory exposure to material and conventional computers for pull-based interactions like focussed schoolwork.

Caroline Steel c.steel@uq.edu.au "Student Perspective on mobile apps"
- estimates about 75% of undergrads use mobile apps for language learning
- primarily for reference or practice, not for communication or task-completion i.e. not for elaborate games or social interaction
- like to see summary of accomplishments, comparison to larger group
- small chunks, pick up where you left off

Isil Boy / Gary Motteram ? / gary.motteram@manchester.ac.uk "Does mobile learning need to move?"
- teachers use mobiles much like previous technologies (laptops) rather then essentially personal device
- i.e. just another distribution channel, rather than exploiting unique capabilities

Frederik Cornillie frederik.cornillie@kuleuven-kulak.be "Seeking out Fun Failure"
- within drilled practice, aim for interesting practice vs demotivating drills
- low-level skills learned on an inverse power law pattern (lots of benefit quickly, but true fluency takes a great deal of practice)
- games take getting motivation out of failure to the logical extreme
- all actions, even if "wrong" have an impact on the "world" you're in
- immersion proportionate to cognitive load, students like immersion in some kind of context but want minimal cognitive load
- best to create at least a very simple "world" which is affected by user behaviour doing practice because
- "vivid" microworld no more motivating than "plain" microworld, both more motivating that simple drill presentation

Heyoung Kim heyoung2010@gmail.com "Effective MALL - implications of empirical analysis"
- students like "light demand" exposure to actual English (level n-1), to confirm fluency
- students choose for content, not academic skills (prefer more controlled environment for learning new, difficult content or language skills)
- ideal is to provide scaffolding (dictionary, media controller, sentence-level chunking/replay) because students overestimate slightly their ability
- even with practice-type material, focus on mastery of already half-done material, rather than challenging material
- students (Korean) preferred audio-lingual approaches and no SMS, collaboration, communication; opposite of preferences stated for non language-learning use of mobile tech

Glenn Stockwell gstock@waseda.jp "Push" mechanisms for out-of-class mobile learning
- exploit small amounts of time and space; expect use to be fragmented and in distracting environment
- assume device is part of everyday life - student has at destination as well as in transit
- does push technology increase use of mobile device
- sent out daily, individualized message to student at end of school day (to catch them in transit home)
- 60% of students turned on push reminders, even though 72% of students used only PC (not mobile) to do homework
- reminders did not increase use of mobiles to do homework, but may have increased use of PCs (further study to be done)
- learners use pull tech (and prefer PC) for planned activities - schoolwork is seen as such an activity
- learners use push tech (mobile) for spontaneous activities, including updates on planned activities