Kanji Connect 
A fun way to learn JLPT kanji/vocabulary!
Provides kanji meanings, readings and example vocabulary

PhraseBot
Use flashcard sets imported from Quizlet, from single kanji up to full sentences

Kanji Crush
Match 3 game  based on kanji form, radical, or onyomi.  Really get to know kanji forms and readings, and distinguish lookalike kanji!