I've been using SailfishOS for 3 years now as my daily driver, never had any problems with calls, sms or mobile data. Roaming or not. It is not a fork of androi

I've been using SailfishOS for 3 years now as my daily driver, never had any problems with calls, sms or mobile data. Roaming or not. It is not a fork of android but if you get the paid version you get android app support on it. At one point I even got microg on it to see if my banking application would work and it did. Officially they support a very small number of phones, I think only some sony models.