I have only had my iPhone for a short time, so I had not seen this app before, but I love it! You can download images and even take a an art quiz (my best score so far: 48170 145/150 in a session time of 12:33 min). I have even been introduced to a couple of artists whose work I had not seen before, all for only 99 cents.

This is not a paid endorsement, it's an art lovers endorsement.