Will re-syncing iPhone to a new iTunes installation delete app data?

You should be able to see all of the Apps in your iTunes library. If it looks OK then sync them. Either way, you will still have the Apps available. Once "purchased" always available.

App data is stored in only two places, on your phone & in your iphone backup. When you do hit the sync button, all itunes content will be erased from your phone. Because you formatted your hard drive, your phone now sees your computer as a "new" computer & since the iphone, by design, syncs itunes content with one computer at a time, there is no way to prevent your itunes content from first being erased from your phone. If the same content is in your current itunes library, you simply sync it back. To preserve your app data, do this:

1. Disable auto sync when an ipod/iphone is connected in itunes, under preferences(under the edit menu if using windows).
2. Make sure your computer is authorized-Store>Authorize this Computer.
3. Make sure whatever contact & calendar applications you use on your computer are not empty-put fake entries in if you want, the important point is that they not be empty.
4. Connect your phone, itunes running, DO NOT SYNC, go up to File>Transfer Purchases-to make sure all purchased content is in your itunes library.
5. Right click your phone in the device pane & select "Reset Warnings"
6. Right click again and select "Backup".
7. Right click again & select "Restore from Backup". Select the backup you just made, if prompted to create another backup, decline.
8. Follow this by syncing your itunes content back to your phone, which you select, as before, from the various tabs.

If you follow these instructions, you will preserve your app data & you'll be syncing to your "new" computer.

Hi,

I know its being discussed all the time, but still I am confused a bit, so sorry for asking, maybe the answear is obvious.

I have a Mac Pro where I synced my iPhone and now I want to sync it with my new MacBook Pro. I have authorised MacBook and have transferred purchases to it, but now when I'm gonna sync it, it will erase everything in iPhone and sync it back. OK but I dont want to lose my progress in games and so on, can I apply the solution wjosten mentioned before?

I wonder if there is some easier way, since I have an OK backup on the Mac Pro. For my wife I used Migration assistant in the mac and transferred her mac account and it works great, but my mac account is way too big, maybe I can somehow tell the Migration assistant to move only certain things, in this case only itunes stuff.

Any ideas? Thanks a lot.

Actually I found this solution http://rackerhacker.com/2008/11/02/syncing-an-iphone-with-a-new-mac-without-hass les/ which I tried and it worked perfectly. I was worried if it works with iTunes 9.2 as the solution is quite old, but it worked!

Hope it helps to the others as it did for me.

The easy answer is to go to 'File' in iTunes, then 'Transfer Purchases from XXXiPhone' This will transfer all your apps to the iTunes app file, then when you check 'Sync Apps' you'll see all the apps from your phone ready to be synced, but not always in the same order you had them originally. That you can change either on your computer or on your iPhone, the next sync will bring them together again.

"The easy answer is to go to 'File' in iTunes, then 'Transfer Purchases from XXXiPhone' "


The easier answer is to ALWAYS maintain a backup copy of ALL your important info/music/apps/pics/docs/etc. This has always been basic and will stop a crashed computer/broken ipod/bad hard drive/software restore/reformat from being a problem.

Basically wjosten's advice worked for me. I had wiped my MBP and installed Snow Leopard but forgot to make a backup of my itunes library. My main concern was the app data. I followed the instructions but chickened out at step 8 when iTunes warned me that it would erase the phone and ..." so I cancelled to just make sure I had everything right but it went ahead and made some weird sync anyway which left about 20% of my apps on the phone. So I restored from that backup I made at Step 6 and this time said ok to the sync at step 8.
But then I checked the sync apps checkbox but either didn't realise or something happened that meant all the apps were unchecked. Next thing I see is "removing {app name}" which started freaking me out. I'm not sure what to do from this point so I started checking all the apps and pressed apply. However, it may work better if you cancel the sync but even better would be to have all apps checked in the first place. In the end end though I didn't loose any data - even on the apps that I saw getting removed just moments earlier. WOOHOO!!
One side effect of this is that the apps are not in the same screen order as before... but that is either my fault or a very very small price to pay 😉
So this method works but you have to have the guts to click ok 🙂
Also, be careful of your voice memos - I'm not sure if the instructions here cover those but they are not paid content so I would make sure you use something like http://www.macroplant.com/phonedisk/ to back them up.

Oh... just found some apps that didn't keep the data.... Not sure if there are different ways that apps keep data but the couple that were really important to me still had all their data but some other ones didn't. For example. RunKepper Pro kept all my training data; MoneyBook all my spending; and aNote all my notes. But Consume, Analytics Pro, Facebook, DropBox lost my account info. But Twitter, Tumblr, Foursquare kept it. I have a feeling it is because I stopped the sync in time before those apps were removed? Lucky!

I can't believe apple is forcing us to lose our data when we upgrade our pc. I simply can't do that.

I am fine with all the steps, transferring purchases, deleting on synch and getting apps again, but the data?!

Data is way more important. What's wrong with apple not supporting data transfer as well as app transfer. It's such a basic and a given and without it is just crippling. I'm so frustrated. Please someone tell me I'm wrong so I can get humble and get this working.

Thanks in advance...

rob

In the end the steps don't loose data either if you make sure, in the final step, that iTunes doesn't start removing your apps because either a) you forgot to check all the apps you wanted to keep in the app panel or b) iTunes accidentally (i.e. a bug) unchecked all the apps and started removing the apps anyway.

When I transferred my iPhone to a new computer I lost some data in some of the apps that got removed before I was quick enough to stop the process and go back and recheck all the apps I wanted and do the sync again.

When I transferred my wife's iPad I was highly aware of the apps and it worked fine and no data was lost.

It is possible to not loose the data, you just have to be super quick to act if it starts saying "deleting {app name} from the iPhone" (or whatever the sentence is, can't remember specifically anymore).

Thank you wjosten.

I followed your instructions to a tee and it worked perfectly.

My old PC to which my iphone was synced and authorized had recently suffered a severe, irrecoverable hemorrhage. I had successfully imported all my third party data manually. But was very concerned over the third party data sitting inside the apps. Your method worked perfectly. Thanks!

Ii find wjosten answer very accurate,,,, but still got two questions for him:
1. what is your solution different from a simple "tranfer purchases "?
2. it worked well but all my apps original order and folder were not kept and when sync again they actually were lost.

tnx
ddtpz