Eloquence is a simple app for learning words with flashcards
The applications attempts to emulate the stack of flashcards that one would normally use for expanding their vocabulary.
You get the word and pronunciation on the front of the card and the definition after flipping it.
Just as with a normal stack of cards you can put them in different piles - "to review" and "done", so you can pay attention to words that give you trouble and skip the words that you already know.