First the person the rated down cause no iPad support is wrong. Its optimized for iPhone but works on iPad just like it says. Its just not scaled up for iPad (yet)
That being said the program is great but missing 1 very key feature which is spaced repetition. Sadly all the audio files, sentences, pictures and vocab in the world wont make this a useable app till they add spaced repetition. Save yourself the Money for now and check back often for spaced repetition addition.
Tip to developers: vocabulary apps are useless without spaced repetition option.
NoRefund17 about GENKI Vocab Cards for 2nd Ed.