How do I test upgrades using Ad-Hoc distribution before I send an upgrade of my app to the app store
From IPhone Dev FAQ
You need to make sure that the appId's are correct and the same between the two versions, and that you change the "Bundle Version" number in Info.plist. (Do a google search on this if you don't know how.)
Testing using iTunes on Mac:
(1) Make sure you have all the certs correctly installed and configured in your project. Here's a good reference:
http://www.24100.net/2009/02/iphone-sdk-mobile-provisioning-0xe800003a-0xe8000001/
(2) drag into the "Library" word in iTunes the ad-hoc mobileprovision file you built your ad-hoc .app with. (It may ask you if you want to replace an existing one, say yes)
(3) drag the .app file into the "Library" in iTunes, say you want to replace the existing one.
(4) sync your device in iTunes
Testing on Windows: You can't. There's a bug. You can only delete any previous versions from *both* iTunes "Applications" library AND from the iPhone/iPod touch. Then after you've deleted the previous versions, you can install a new version. (Apple knows about this bug, but I doubt it has high priority.)
