There are good and save keyboards in F-Droid, but, well, the problem is Android itself. F-Droid is essential to obtain apps which respect privacy, but this only patch some holes when Google itself control the entire OS.

Mobile phones and privacy is an oximoron, because of this, I never use my phone for important data.

• Review apps on Exodus Privacy
• Desactivate GPS/Localisation service, at least if you dont use it
• Review permissions of all installed apps and set them to desactivate after use in the app settings
• Disconnect WiFi when you go offline
• Don’t use public WiFi, at least without VPN, even if it is only a free one (eg. like Calyx, FOSS, trustworthy, no account, encrypted, without datalimit, but only 1 server from the Calyx institute, anyway save enough for an occasional use, Techradar review).
• Common sense (the user is the biggest privacy hole)

I haven’t installed something outside of it for ages. I used the foxy client for a long time, and recently droid-ify