Videos for this would be really cool!

Here is a list of apps: https://pixelfed.org/mobile-apps

I believe the official android app is open source, and the latest version is in open beta on the playstore, but you may need to add the repo manually to get it from Fdroid. I’m using the playstore version myself.

There are a few unofficial apps too, I can see PixelDroid listed in FDroid