An eye-opening article in the Wall Street Journal details the extent and kind of information that your apps collect about you and share with advertisers. In their tests of 50 different iPhone apps, they found that Pandora, for example, sent age, gender, location, and phone identifiers to various ad networks. It's a bit scary. According to the article, Apple says that they review apps to make sure that you're asked your permission before certain kinds of information, such as your location, is shared. But the WSJ found that this policy is skirted, and that the game Pumpkin Maker, for example, sends information about your location to an ad network.