In trying to find ways to incorporate smartphones into the classroom, I have been experimenting a great deal with spaced-repetition system (SRS) flashcard apps. Since I am a heavy user of the Anki program/app and know it well, it has been the main focus of my classroom efforts for the last two years.
However, due to the cost, I cannot require my students to buy the Anki app. Instead, the students have been using the Anki website to create and study cards. It is not an ideal solution but a functional one.
Recently, I have been looking for alternatives to Anki. Unfortunately, many of the free apps leave something to be desired.
However, just the other day, on an excellent website called Flashcard apps for for iPhone & iPad, I discovered a distinct possibility called Flashcard Elite.
I have only downloaded it today and am trying a JLPT N2 (Japanese level 2) deck. So far it looks pretty good! I'll report more later after I've used it some more...