I downloaded a free application several weeks back that streams a local radio station I really like. When the apps were transferred to my new iPhone 4, the radio app no longer worked. I wrote the development company and asked them if they had a solution or an update. Here is what they wrote:
"Did you try transferring your apps from your previous iPhone? iTunes doesn't do a good job of moving it. Please follow the steps below to fix.
First, check that the app has been downloaded to iTunes, then:
1. Delete the radio app from your iPhone (or iPod Touch or iPad).
2. Power off your device (hold down the wake/sleep button until asked to "Slide to Power Off"), and then power it back on.
3. Reinstall the app to your device.
4. Start the app.
Let us know if you continue to have problems after following these steps.
AirKast Support "
The solution they provided worked, and the app started right up. They also provided further information...
"We're putting it on our website and FAQ pages, and notifying people as best as we can. We are not the only developers having this problem; some other apps have similar issues...and our reinstall steps would work with them too."
I hope you find this tip as helpful as I did.