Today the iOS 4.1 beta was released for the developers and the iPhone 3G, 3GS and 4 and iPod Touch can be updated to this latest software. If you want to update iPhone 3G to iOS 4.1 beta, then here is how to do it. Just follow the below instructions to update iPhone 3G to iOS 4.1 beta.
1. Download iTunes 9.2 from here.
2. Download the iOS 4.1 from here.
2. Now connect your iPhone 3G to the computer.
3. Choose your iPhone 3G device from the list in the left.
4. By holding the Shift key (in Windows) or Option key (Mac OS X), click on the ” Restore ” button.
5. Now browse to the downloaded iOS 4.1 beta .ipsw file and choose it to update your iPhone 3G to iOS 4.1 beta.