Missing on website: how to backup app-data (and later restore on /e/)

Summary

https://e.foundation/get-support/ once said to start with step "1. Backup your data", but there were no instructions which app to use, etc. Currently it only points to a new installer or the download page.

However, there is at least information missing on how to backup current app-data (and to restore it on /e/ later).

What is the expected correct behavior?

Provide instructions that explain how to install a backup app (from f-droid?), and do the backup and later the restore on /e/.

There seem to be different parts to this:

• SMS/MMS/Call history: https://gitlab.e.foundation/e/apps/eDrive/issues/55
• App data: non-root backup app???
• Accounts?: https://gitlab.e.foundation/e/management/issues/338

Maybe also release the /e/ backup app to the pay store, to let it do the backup and find and recommend free replacement apps where possible?