Peter wrote:
You re-download them all from the app shop?
Yes. But they’re all downloaded automatically.
What about the apps which were withdrawn from the app shop in the meantime?
VLC on IOS, anyone? 
I’ve never had an app that was withdrawn. You can install apps yourself by downloading .apk files. OziExplorer is installed that way for some obscure reason. Not how it should be done.
VLC is in the Google Play store.
I don’t know. While I like Achim’s modern “leave yesterday behind” attitude, I also like to have many things on my iPhone locally so I don’t need cloud access to get them
- all my airplane manuals in Good Reader
- my music
- all the navigation apps for flying and driving (TomTom, Pocket Earth …)
I have about 3 GB TomTom Car maps on my phone (Europe, USA; Japan …) , which i cannot upload to the cloud, and wouldn’t want to
Yes – I have TomTom too and it is a few GB. However they seem to compress very well. I have just backed up everything with both MB and TB and it comes to 4GB.
The issue of a “total backup” (backing up apps and their config etc) is obviously intimately linked to software piracy. Nobody who wants to create an ecosystem run an app shop on which they get commission on the paid apps is going to allow a “total backup”, on a device which is either unprotected or is trivial to jailbreak like Android is. Any such backup could be restored to N other devices which will all get bootleg copies of everything.
Apple were able to deliver a “total backup” because
So maybe I should not be surprised.
And I bet some apps stick some bits in non-obvious places, so that even a rooted-phone restore does fail to run after all.
The TT data cannot be backup up (without rooting) for the above reason. It’s an expensive app, relatively.
Nokia had the same dilemna. Of course Symbian is irrelevant today, but a lot of apps were IMEI-locked. And the “app no longer in the shop” was a big problem.
Just to be clear, apps are not backed up on iOS. When you restore from a backup, the apps are restored from App Store (or iTunes) just like on an Android device. It’s not a ‘total backup’, rather it appears to be because it is well implemented.
Apps absolutely cannot write anything outside of their individual sandbox, so it is trivial to back up and restore correctly.
If you have any apps which are no longer in the App Store, the best thing to do is use iTunes rather than iCloud. When you plug in your device, it will offer to transfer purchases to your local iTunes library, and they can then be restored onto other devices you own.
And what does the iOS backup do about data written by applications into their directories?
Backs it up ;)
It’s quite complex, but in a nutshell:-
‘user generated’ content is backed up. So this would be documents / config files and whatnot
‘caches’ are not backed up. This is stuff that could be downloaded again or regenerated
This is stuff that could be downloaded again or regenerated
That could be mapdata for a GPS satnav app, presumably? (as was common practice before a specific IOS version started silently deleting the cache data).
Well, sort of. Your mapdata doesn’t need backing up, but it also mustn’t be deleted on an adhoc basis by the OS when it is running out of space.
You can can have user data which isn’t backed up, but will not be purged by the OS. You do that by putting it in the application bundle’s ‘documents’ folder (which would otherwise normally get backed up), but set the ‘do not backup’ flag on the files.
Stuff that’s in the ‘cache’ folder can (and does) get purged by the OS outside of the control of the end user, so you absolutely mustn’t put things in there which your app cannot run without.
