Failures:
1) If you're building a language app, you provide audio.
2) At the very least, if you can't manage recording a native speaker, (which should make you reconsider providing a language app in the first place) you need to provide proper IPA transliteration. ESPECIALLY for English speakers. There are dozens of English dialects, and the examples provided can be pronounced many different ways.
3) If you're going to provide a "lite" version of an app you expect people to pay real money for, you need to provide common conversational words and phrases, not a random selection of "a" and "b" words.
4) "300+" words is useless for any language flashcard app. Maybe you'd be of use if you provided 300 essential words for beginners, but unless it's essential phrases for beginners or travelers, you've missed your mark. Beyond that, if it's vocabulary building for intermediate speakers, then you've already surpassed your target market.
Better go back to the drawing board...
DELETED.