The idea is that every time you try a new wine, you snap a picture of the label and leave a short note about what you had it with, how it tasted, or where you got it. Then, later on, at the liquor store or when out at a restaurant, you can pull up "that wine we tried last week," and you'll know exactly what it was. It's simple, but it's perfect for people like me who aren't wine experts and need a little help remembering exactly what that last bottle was called.
Unfortunately, the app isn't perfect; I don't like that you must log in on startup, and there are quite a few features (like a wine database or the ability to browse friends' wines rather than just "nearby" check-ins) that seem like they would be awesome but are still missing from the app. The basic functionality of tracking your own wines is well worth the 99 cent price, though. Maybe this will finally give me the method I need to start developing a more refined wine palate.