Restoring to an older iPhone?

[jent]

I have a factory-unlocked iPhone 4 and I really enjoy it. I travel fairly frequently, and I'm thinking of using my AT&T upgrade to get a factory-locked iPhone 4S.

For future trips abroad, I was wondering how the process would be of using my iPhone 4. Can I restore an iPhone 4S backup to an iPhone 4? If so, would it be wonky?

 

[DirtySocks85]

I have a factory-unlocked iPhone 4 and I really enjoy it. I travel fairly frequently, and I'm thinking of using my AT&T upgrade to get a factory-locked iPhone 4S.

For future trips abroad, I was wondering how the process would be of using my iPhone 4. Can I restore an iPhone 4S backup to an iPhone 4? If so, would it be wonky?

While I've never tried this exact situation explicitly, I'm fairly certain that Apple does a few things to safeguard it from getting "wonky". My guess is that if iTunes allows it, it should be fine. Remember, worst case scenario is that it does get a bit wonky and you just have to restore the iPhone 4, which if you have a backup of the iPhone 4 as it currently is, shouldn't be a problem.

 

[sanford]

I have a factory-unlocked iPhone 4 and I really enjoy it. I travel fairly frequently, and I'm thinking of using my AT&T upgrade to get a factory-locked iPhone 4S.

For future trips abroad, I was wondering how the process would be of using my iPhone 4. Can I restore an iPhone 4S backup to an iPhone 4? If so, would it be wonky?

I can do you one better than a 4S->4 restore, with direct experience. My iPhone 4 was stolen a few weeks before the 4S was available, so rather than immediately replace the 4, I waited and bought a 4S. In the interim I switched back to my old, spare, give-to-kids-later 3GS. I had to drop by an AT&T store and get a new SIM for the 3GS, though that won't be a problem for you since your 4 is unlocked, and you haven't had to deactivate it due to theft. Went home, restored my 3GS from my latest, very recent iPhone 4 backup. Only thing I noticed was the LED camera flash flashlight app I had didn't copy over to the 3GS, because, of course, the 3GS has no LED camera flash. And it even warned me about that.

My experience: very safe, no wonky. Just do a sync AND a backup right before the restore (right after would be a good idea, too), so you don't drop a couple texts or whatever you thought you'd never need but find out later that you do.