Go to your phone homescreen and look at the app dock (the bottom row that contains some apps and stays the same when you switch pages).
Which are yours? Any FOSS apps?
In my case, they are FDroid, Signal, Threema, Firefox and the defaul Samsung camera app. So, 80% FOSS…
Yes! It’s bonkers that they did not yet do it
I also think that they should work with the same backend and similar frontend. But they rather pay 5 people do to the same job