I have been having some problems with my iPhone 3G. Nothing big, but it still affected me. Every time I would try to open a application, and the phone would go back to the home screen. This happened on every application I downloaded from the App Store. I sent out a Twitter message, and got a reply from Aaron (@sonictonic on Twitter). He forwarded me to this MacRumors iPhone Story.
Several people have described a problem with App Store applications after restoring from a backup. When your applications are launched on your new iPhone 3G, they will only show the start screen and then immediate quit.
The issue may lie in the Digital Rights Management embedded in each of the applications. In order to restore functionality, you simply need to delete the applications from the iPhone itself, and then resync the applications from iTunes. Once restored, the applications should launch properly.
To delete applications from your iPhone, you simply press and hold on one of the icons. All the icons will then start jiggling. Simply click the “X” in the top left hand of the application and it will ask you if you want to delete it.
Note that even if you delete an application entirely from both your iPhone and your iTunes install, you can still re-download it for free. This is true no matter what the price of the application was.
[via MacRumors iPhone Blog]
Thank you very much, Aaron and MacRumors. My iPhone is back to normal now.
Daniel Brusilovsky 
I tried that…even tried restoring, then resetting – problem persisted.
I have narrowed it down to being a problem with having the last.fm or loopt apps being installed – ended up formatting to factory settings as a last resort.
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Yeah I have had that same problem except on my iPod Touch.
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tell me about it, i am have all kind of problem with the phone, it crashes everyday now.. is the update coming out?
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Hey Kevin,
I just updated my iPhone to 2.0.1, and it seems fine.
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I had the same problem with my iPhone 3G, all my apps from the app store were crashing after the start-up page. So I deleted loopt and restored to factory settings, now everything is working great! Thanks Anonymous! I would never have thought of that.
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I have the problem with my iphone 3G everyday, it crashes everyday with the app. I took my iphone to Apple store to talk with, so called Genius, and they had to do force recovery. To syn. everything back to my iphone takes a whole night everytime.
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