iFlash is an advanced memorization application based around the flash-card learning metaphor. If you want to learn almost anything, from a foreign language to the ten-codes police officers use, iFlash is for you.
iFlash includes many great features to help you study. You can record audio directly into any flash-card (great for foreign languages), as well as attach images. Other features include an unlimited amount of card sides per deck, advanced importing and exporting, iPod support, quick-searching, and a beautiful interface that is strikingly similar to other iApplications (like iTunes and iPhoto).
Also included is the integrated iFlash Deck Library, which is an easy way to download and share card decks. With a familiar interface and close to 2000 card decks available, you'll be learning something new in no-time.