mega.nz Android app is open source on Android. Please add this app to the official F-Droid repo. It is a good cloud service that uses E2EE encryption and has been around for years.
Inclusion requests are tracked here: https://gitlab.com/fdroid/rfp/issues. Looks like Mega source code is not completely open, it includes proprietary Google Play Services bits: https://github.com/meganz/android/blob/master/app/build.gradle. So it does not comply with our inclusion criteria.