Also see Google's New Wireless Service Should Make Verizon and AT&T Squirm (MIT Technology Review) and Google’s Wireless Service: What It Means for Consumers, Google and the Carriers (Re/code)
"But the founder of another wireless upstart thinks that’s just fine with Google. “They’re not trying to massively disrupt,” said Stephen Stokols, president of FreedomPop. Instead, he thinks it’s a replay of Google Fiber, the company’s superfast Internet service. It’s available in just a few cities, but Google Fiber’s popularity is goading major broadband companies to boost their network speeds, making Google’s online offerings more attractive.Cheap, simple cellular? Google answers the call - Business - The Boston Globe
FreedomPop offers features similar to Project Fi, such as phone calling over Wi-Fi networks and the right to roll over unused data bits. But Stokols thinks Google’s biggest innovation is a phone that can switch between multiple carriers."