The developer was not exaggerating when he said this app was powerful and could be addictive. In my opinion, it is much better than Cram, Vocapp, Flashcard Deluxe, etc., and better than Ankidroid and Quizlet if you want to enlarge your vocab in a more entertaining way. I was skeptical when I first saw its relatively crude UI, but soon I found it the best flashcard app I ever used.