Since Google’s Project Fi launched in 2015, it has quietly been one of the best deals in tech.

Project Fi is getting a new name in the process: Google Fi. The best news is it will begin accepting most recent Android smartphones and iPhones running iOS 11 or higher.

Google Fi is an MVNO, which stands for “mobile virtual network operator.” That means it doesn’t operate its own network; your actual service comes from larger carriers; Fi uses T-Mobile, Sprint, and US Cellular as its backbone. Letting its users jump around to whatever network works best for them wherever they are.

This leaves open a few questions. How does the Google Fi service determine what network you will use when you’re on cellular? Are you stuck with whatever cell network you dropped into when you first came off of wifi? If you can’t transition to wifi for calls and texts, does that mean you’ll end up using more data? What about Apple Watch cellular plans?

Formerly Project Fi, it’s Google’s “pay for what you use, month-to-month” cell service. There are no contracts and you pay $20 for unlimited talk and text per month, plus $10 per GB of data used. Even nicer, when you pay for an extra GB of data, but don’t use it all, Google will give you a credit towards your next month of Fi equal to the unused portion.

iOS compatibility is technically in beta, so anticipate a less-than-smooth experience. It requires “a few extra steps to get set up”. There will be a new Google Fi iOS app to help ease the process along. You will find that Visual Voicemail won’t work anymore, but iMessage will.

If your phone is on the list of the compatible phones and interested in switching over to an inexpensive, transparent, no contract cell service, today is a great day to do it. For a limited time, Google Fi is offering the price of any phone you purchase back on airline flights or Airbnb and purchases. If you’d rather bring your own device, they’ll give you a $200 service credit (which, depending on how much data you use, could last you a very long time).

The real appeal of Google Fi has always been its simplicity and affordability, both of which remain no matter what device you bring on board.