All 3rd party apps crash after 3.1 upgrade iPhone 3G

Having exact same problem. Tried power cycling and resetting all settings, to no avail. I suppose that the next thing to try is a complete restore. Really annoying. My guess is that somehow some DRM setting got messed up and now the phone doesnt think I have the right to run the app Im trying to run.

Same thing here. Just started tonight, though the phone has been flakey lately.
Weird that its just all of a sudden happening!
iMac 2.4 iPhone OS 3.0.1 4GB RAM

Same problem...what gives?

This phone is great....when it works. $300 for a headache...

Ditto here. extremely frustrating. I'm not finding anything on the other blogs re this - anyone else having any luck??

Same problem here but on 3GS. I believe it is related to the sync to iTunes. My third party apps start working after I either a.) update any app b.) download a new app. I have the phone for about two weeks and it was fine. Then I downloaded iTunes, synced the phone and updated the firmware. The third party apps stop working after a synch. Someone suggested downloading a small simple app like the flashlight to get things working again. This works, but what a pain for a $300 phone.