Web apps.

For reference I work for a competing mail provider and the majority of our users don’t use SMTP or IMAP, instead exclusively using the web app.

You can also use systemctl status $pid to find out what service a process is from.

I used to turn to custom roms to extend the life of my phone. My first smartphone didn’t get an official update after I purchased it for example. The custom roms often made the phone snappier too.

These days I’m on a mid range Samsung phone released almost 4 years ago and it’s still getting updates.