Librerian

It does lack a few features though, as they rely on proprietary software/libraries. Android Auto for instace, as well as ANT+ for connecting sensors. At least for those features you need the Google Play version.

You need to be unplugged for 12 consecutive months for Proton to delete your account because of inactivity though, which seems fair for free tier accounts. A simple login is enough to prevent this, you do not need to send an email or whatever, simply log in once a year. You also get reminders sent to your recovery email before this happens. Data storage for inactive free tier accounts isn’t free for Proton.