1, lacking automatic text-to-speech play option compare to "flashcards" app. 2, No reminders compare to the other app which I forgot name 3, No "dont know", "not sure", "know" evaluation in test section compare to "A+ pro" app 4, lacking multiple language support when setting "text-to-speech" for each side of flashcards. 5, lacking "copy" and "group cards copy" button when edit flashcards 6, not support 4 inch iphone 5 screen yet 7, lacking pictures input as marks for decks or group name when browsing 8, after having those Improvements, this will be the best memory enhancing app, and can sell 4.99 :)