The only way to do a truly full backup of apps and their data is to have root access. Unfortunately, many phones these days have “security” features that void the warranty and/or break apps like banking, Google Wallet tap-to-pay, etc. Or even some apps like games that rely on that for anticheat will break. And some security features make that last even if you relock the phone. So be careful to read what your phone has and what you’ll be permanently giving up.

I have a Pixel 10 and installed GrapheneOS which has some backup capabilities built in, but I can’t use Google Pay, some banking features, a bunch of games, the official UPS app, etc. But if I gave in and went back to Google Android it would all work. Samsung and other manufacturers are often not as generous.

I’m in a similar situation. I did inidvidual backups for each app that offers such a feature and copied them into a hard drive with all the photos and other files that I need. It’s arduous the first time but it becomes easier the next time you do a full backup. I have an organized folder which contains subfolders for each app and for photos, downloads, etc. All backup files are exported into their respective folder. It takes me all in all up to 15 minutes.

I use DataBackup (app on fdroid) for that. It does need root tho. But it makes it so incredibly frictionless to switch phones.

A lot of programs have an export button for settings a such. Useful for your launcher and whatever else has a lot of settings.

I don’t like doing a full restore, new phones are a good time to clear old system files and crap.

For syncing stuff, I don’t use most of the default phone folders for docs, music, etc. I make my own for everything, so if some update or app decides to do some shenanigans to those folder none of that is backed up. Only folders I don’t make are downloads and photos, and dcim, which I still backed up.

If you don’t want to deal with a syncthing or something automatic, you could try “Back In Time” on Linux.

I believe you can use the command-line tool “adb” for this. It’s been a while since I’ve done it since I use syncthing now, but here’s a quick intro:

1. on phone, enable developer options
2. on computer, install android tools, which should come with adb (Do not install full android developer toolkit, it’s huge. You only need adb)
3. on computer run ‘adb devices’, which should currently print that no devices were found
4. plug phone into computer, and accept authorization prompt on phone
5. on computer run ‘adb devices’ again and it should list your phone with the status “authorized”

Now you should be able to use adb pull -p -a <folder name> to back up folders to your computer, for example adb pull -p -a /sdcard/DCIM.

Note that you will have trouble backing up the /sdcard/Android folder, which contains a lot of app data. Unfortunately I think you need root to back up that folder. Alternatively you can back up individual apps using adb backup ….

Personally I think in the long term, automatic backups like syncthing is better. Manual backups are a hassle and because of that, you won’t do them as often.

i use titanium backup because i use old android. i think swift backup is the recommended alternative now. you need root for this tho.

there’s a recent linux kernel vulnerability that allows temporary rooting so you might be able to use it if you haven’t installed os updates since april this year or so