I wouldn't mind some advice as well - basically I have no interest in owning a smartphone, but practically everyone in my country insists on using a proprietary, facebook-owned chat service that's restricted to smartphone users only (Whatsapp).
I've recently been getting by using a feature phone that has Whatsapp support, but they're discontinuing support at the end of the year, so I need to get something else.
Is it possible to install it on a de-googled Android fork (or whatever alternative OS) or would I have to use official Android? (e: apparently yes, I answered my own question by reading the Calyx website, very helpful)