https://www.theregister.co.uk/2018/11/29/google_project_fi/

Google has loosened its stranglehold on Project Fi, expanding its US cellphone network service beyond its own handsets to competitor smartphones made by Samsung and Apple.

But, be warned: check the supported features before you sign on. And also ask yourself if you want to jump on a network run by one of the hungriest personal data scoffers on the planet.