Since iOS 5 was first in beta many developers started complaining about the fact that the [[UIDevice currentDevice] uniqueIdentifier] got deprecated.
Some developer even stated that is was the worst idea Apple ever had.
Well I don’t agree with them, this is about the smartest thing they did. If only for the privacy of the user.
Let me explain my self, I’ve bought a second-hand iPhone 3GS to replace my old 3G.
The previous owner wiped the device clean, like you should when you sell it.
But as soon as I started to install some apps, it was clear that the device was linked to the user. A game pre-filled the user name, which was the username used by the previous owner. Definitely the sort of thing you want.
Well I’ve yet to find an app that gave me more personal information about the the previous owner. But what if the Facebook would let me login because it checks the UDID.
It seems that there are many games that do this and it is just wrong.