iPhone 13 upgrade / restore gone wrong

[Bento.Box]

Hello,

unfortunately, my iphone 12 mini's display died spontaneously (flickr, tint then unreadable). Because apple care ran out last month (bad luck), I decided to upgrade to the current iphone 13 mini with 512GB and get a 5 year 3rd party warranty (cheaper than apple care and longer duration).

For some reason, the new iphone could not import data from the old iphone, despite the other one still working (except display) and being connectd by wifi, bt and cellular.
I had to restore it via itunes, which was a bit tedious because I needed to set it up as new phone first in order to install ios upgrades and then deregister/wipe it again before the restore procedure would work.

Because of the slow lightning connection, it then took a while, but showed no errors and worked mostly fine.

The apps were not restored, but redownloaded from the internet - which is fine since I have a fast internet connection. But it would have been nice to offer an option to include apps in the backup.

However, many apps experienced data loss. Again, no errors were displayed, but the data was mostly gone and I had to perform disaster recovery (which I was fortunately prepared for). Mostly banking apps and wallets were impacted, but other apps were restored just fine. itunes even pulled the SMS off the sim card and restored them on my new phone. For Threema, the data loss was partial, as it didn't have the ID anymore, but all the history was there. Same for one of the supermarket apps, the login data was present but somehow the payment data got corrupted.
Only one app actually noticed the data corruption, which was the swiss covid app.

My question: Is there a systemic reason behind those data corruptions? Did I configure something wrong in itunes? Did some devs mess up and somehow managed to exclude their app data from the backup? How can I check in itunes if a backup is completely valid?
Is it better to use 3rd party programs for backup (if yes, what do you recommend? I don't want to jailbreak it).
I did a restore test on my iphone 12 back when I got it and didn't notice those data corruption issues. However, I didn't do it with a full set of apps, the phone was pretty vanilla.

Also, is there a procedure to upgrade iOS without creating an account and linking the phone?

It's not that I lost something important, but the whole restore procedure took a lot of interaction and time spend to check dozens of apps and restore access. I know smartphones are (still) not as easy to handle as PCs and servers, but I'd like to improve the experience for the next time.

 

[chabig]

For some reason, the new iphone could not import data from the old iphone, despite the other one still working (except display) and being connectd by wifi, bt and cellular.

I think this sentence is all you need to know. The old 12 Mini wasn't working properly. Going from a normal phone to a new phone is seamless.

 

[Paddle1]

Sometimes there are issues with a specific backup. I would then try restoring with a different backup or method such as iCloud instead of iTunes or vice versa.

Additionally some more sensitive data isn't transferred with iTunes if you aren't using encrypted backups for security reasons.

 

[Bento.Box]

I think this sentence is all you need to know. The old 12 Mini wasn't working properly. Going from a normal phone to a new phone is seamless.

It was working properly, except for the screen.
Apps were still running, it was reachable via wifi and I could call it.

The new phone didn't ask for something like scanning a QR code on screen that would prevent it from synchronizing.

 

[Bento.Box]

Sometimes there are issues with a specific backup. I would then try restoring with a different backup or method such as iCloud instead of iTunes or vice versa.

iCloud is not an option for me, as it has only 5GB of storage, while the amount of data on the phone is around 150GB (not including apps).

What other backup software do you use/recommend?

Additionally some more sensitive data isn't transferred with iTunes if you aren't using encrypted backups for security reasons.

Backups are encrypted in itunes. There was also no message indicating that it could not backup some data from some apps, which is what I usually see in the logs of other backup solutions (e.g. Spectrum Protect) when something fails.

I can understand why, for legal reasons, sensitive data would not automatically backed up to the cloud, but this was a local backup.

 

[Paddle1]

iCloud is not an option for me, as it has only 5GB of storage, while the amount of data on the phone is around 150GB (not including apps).

That wouldn't be a problem, with iOS 15 or later you can get free (temporary) extra iCloud storage to make a backup when moving to a new device in the Settings app. Of course this isn't useful since the 12 is broken.

I don't generally use anything other than iCloud and iTunes for backups because whenever I've run into a restore problem with them the other one fixes it.

My best guess is either the backup or restore got corrupted in some way or the information for whatever reason can't be successfully transferred to a different device (via iTunes at least).