postmarketOS is still in development, so you may not be able to replace your day-to-day mobile operating system with it. But how about finding an use-case that allows you to use postmarketOS for certain activities on a regular basis? Smartphones are not only about making calls - what about listening to music, podcasts, showing information displays and what not?
Time to chew on our own dog food. Create a new user page with your use case and add the
[[Category:Dogfooding]] tag to show us what you're up to.