Previously, only new Google Fi subscribers on iOS could use eSI
Google is rolling out the ability to use Google Fi via eSIM for existing customers of the cellular service on iOS, assuming their iPhone supports it (via 9to5Google). You’ll need the latest version of the Google Fi iOS app and an iPhone XR, XS, XS Max, 11 series, or 2020 SE, as those phones offer Dual SIM functionality. Google added eSIM support for new Google Fi customers last month.
Although the release notes for yesterday’s Google Fi iOS update say that “you can now activate Fi via eSIM on select iPhone devices,” some Google Fi users on Reddit have had to uninstall their Google Fi app and follow the instructions on the Google Fi website to add a cellular plan to their iPhone to get eSIM to work. Google hasn’t replied to a request for comment about when eSIM for current Google Fi customers on iOS might be rolled out more broadly.