It looks like iPhone users are not immune to the types of data leaks recently discovered on the Android platform. Researchers looked at the top free applications available from the App Store and discovered that '68% of these applications were transmitting UDIDs to servers under the application vendor's control each time the application is launched.' The iPhone's Unique Device ID, or UDID, cannot be changed, nor can its transmission be disabled by the user.

http://apple.slashdot.org/story/10/1...ique-Device-ID