I'm not sure how it works exactly, but Google's own cellular company, Google Fi, promotes the fact that they use WiFi when available, even for phone calls, but can switch quickly to cell when needed. Phone calls are not interrupted when switching. I especially like this setup because my cellular reception is poor at work, but I can use my employer's WiFi to receive calls and data. Phone call clarity is better on WiFi than cellular but sometimes there is a bit of lag that reminds me of calling overseas using geosynchronous satellite connections in the 90's.
Great prices also. Since I'm almost always using WiFi, the $20 a month for global unlimited text and phone calls with a $10/gig data rate means I only spend about $25 a month for my smartphone service. You can only use a subset of Google phones, but I find my Nexus 5x fits my needs. I also always get Android updates right away, if I want to install them.
Great prices also. Since I'm almost always using WiFi, the $20 a month for global unlimited text and phone calls with a $10/gig data rate means I only spend about $25 a month for my smartphone service. You can only use a subset of Google phones, but I find my Nexus 5x fits my needs. I also always get Android updates right away, if I want to install them.