Project Fi is Google’s first venture into the mobile service space. It teamed up with Sprint and T-Mobile in the US to form an MVNO network exclusive to the Nexus 6, Nexus 6P, and Nexus 5X.
The only way you could sign up for a Project Fi account was by either buying a Nexus device through Project Fi’s website, or signing up for an invitation with your Gmail account and waiting a couple of months for your invitation to roll in.
