Say, I remember that thing...
Glad to see it worked out.
It's a great phone. But when someone upgraded to a 4s and offered his 4 at a great price with double the memory and a camera w/flash, I jumped on it.
Ironically, when the 4 arrived, even though he supposedly cleared the phone, a lot of his personal info was on it....just like the 3GS when you sent it to me. He did leave his old SIM in the phone (AT&T gave him a new one), but I didn't think the SIM was used to store anything beyond phone carrier data.
My best guess is that he reset the 4 and left it attached to iTunes. That might have resulted in iTunes restoring lost personal data but not restoring customized files and apps. Guy works in the hotel industry. I could have had a lot of fun if I had a mean streak.