It has the vocabulary of both Genki books. Works by the three stack system. You can also listen each word and in an example sentence, too - an excellent feature!
It was made by people who really thought of the aspects of vocabulary learning. It has also lists of the vocabulary and you can retrieve a word back into the learning list, if youve forgotten it in the meantime.
Ive never saw a more thought about and complete vocabulary learning app!
Heliogobald about GENKI Vocab Cards for 2nd Ed., v1.0.1