If you're an Android enthusiast, you likely know about Project Fi. But that doesn't mean you necessarily know everything about it. And for everyone out there who doesn't have one of the handful of phones that work with the carrier are unlikely to have looked into Project Fi deeply. So we're here to give you the high-level view at the carrier option that comes directly from Google. Namely, just what the heck it is, how it works compared to other carriers and maybe a few reasons why you'd want to try it.
What is Project Fi?
At the highest level, Project Fi is a phone carrier operated by Google. It works by giving you mobile data service on three mobile networks, which your phone will intelligently switch between — it also uses Wi-Fi to make calls and send texts whenever available. Project Fi is a "prepaid" carrier, meaning you pay upfront for your service in the trailing month, which is the opposite of a traditional carrier (Verizon, AT&T, etc.) that bills you after you use the service.
It's all about simplified billing with no hidden fees or overages.
Project Fi is focused on simplified billing. You pay $20 per month for unlimited talk and texting, and a flat rate of $10 per gigabyte of data used. At the start of each month you simply estimate how much data you'll use (by the gigabyte) and pay for that amount — at the end of the month you'll receive either a refund for data you didn't use, or pay a little extra on the next bill for data overages. You'll always pay at the same $10 per gigabyte rate either way. Bill Protection applies to international data usage the same as home usage.
The only time that doesn't apply is when you hit a level called "Bill Protection" — effectively an unlimited plan tier for Fi. Once you've used 6GB ($60) of data in a given month, your bill is then capped at that point for the month but you continue to get data service. You can use as much data as you want for the month without paying over $80 total ($20 base + $60 data). The only caveat here is that once you hit 15GB of total data usage, your speeds are slowed to 256kbps — alternatively, at the 15GB point you can choose to start paying $10 per GB again for full-speed data if needed.
The huge benefit here is that you don't have to pay for an "unlimited" plan every month — it's simply there if you use beyond 6GB of data in a month. All other months when you use less than 6GB of data your bill will be less than $80.
You can also set up a "Group Plan" on Project Fi for up to six people to share a single account and billing source. With a Group Plan, all of the same features of an individual plan apply, but you save $5 per person per month on the base plan charge. Billing is handled centrally by the account owner, along with data limitations for each user (if needed) — Bill Protection data usage limits are also handled on a per-person basis. Project Fi charges the group owner for everyone's bill collectively, but can also facilitate payments back to the account admin from each member to pay their share. Individuals can come and go from a Group Plan as they wish, without any contract.
Unlike most other prepaid carriers, Project Fi is available for just a handful of phones: the Google Pixel 2 XL, Pixel 2, Moto X4, Pixel XL, Pixel, Nexus 6P, Nexus 5X and Nexus 6. You can also use a data-only SIM card with any tablet that supports the T-Mobile network.
How does it work?
Project Fi works with a special SIM card — and a little software on your phone — that can authenticate you on T-Mobile, Sprint and US Cellular, and switch between them on the fly based on a variety of factors. On the new Pixel 2 and 2 XL, an integrated eSIM lets you use Project Fi without a physical SIM card and quickly switch between Project Fi and another carrier's SIM.
Using Wi-Fi for calls and texts, you can keep using your phone in places where mobile data isn't that great. Extra software called a "Wi-Fi assistant" will automatically connect your phone to open Wi-Fi access points when you're out of the house, reducing your data usage without any intervention on your part.
You get the power of three mobile networks, plus Wi-Fi, in a single SIM
When you use Project Fi, you also get some of the same features that have made Google Voice popular over the years. You can forward phone calls to your Fi number to any phone you want, as well as view voicemail, make calls and send texts with that number from any device using the Hangouts app and website.
Project Fi also works internationally in 120 countries around the world with no additional cost for data use or texting. You can call at a flat rate to any number while on the cellular networks abroad, or pay much lower rates when calling on Wi-Fi. You can also call back home to the U.S. on Wi-Fi for free. Data used internationally just comes out of your standard $10 per gigabyte bucket, but speeds can vary depending on the country you're in.
Why do I want it?
Well, this is really a personal question of whether you actually want to try Project Fi. Chances are if you're reading Android Central you're at least one step closer to being the target audience for the Google-powered carrier, but there are a few other boxes to check that make it the right choice for you.
Simplicity in the service and billing are paramount to the experience.
The only big issue for most people is the limited phone choices. Google lets you use its latest phones, the Pixel 2 and Pixel 2 XL, on Project Fi, or you can bring one of the last three Nexus phones — the Nexus 6P, Nexus 5X or Nexus 6. For a modern but mid-range option, you can get the Android One Moto X4. But that's it.
If you're okay with that limitation, you don't have many other hurdles to jump over. You can sign up for Project Fi online in minutes, and you can either buy a Pixel phone at the same time or Google will send you a SIM card to put in your existing Pixel or Nexus. Once it arrives, you can start the typical porting process of bringing your current phone number to Fi, or can start fresh with a new number. You can use Project Fi for as long or short as you want, as there aren't any contracts or commitments involved.
There are lots of cool features that make Project Fi a good choice, like the simplified billing, included international features and improved network coverage through the use of three carriers and Wi-Fi networks. Each one will have a different amount of draw for different people, though.
Project Fi's pricing isn't dramatically lower than other carriers out there, and whether it makes a good choice financially for you depends on your data usage and which features you want. We encourage you to do your pricing research before choosing which carrier is the best.
And whether you're still on the fence or just curious about it, be sure to follow all of our Project Fi coverage here at Android Central!
Update January 2018: Refreshed with the latest links and information on Project Fi plans and pricing, including Bill Protection.