Originally Posted by
TWA884
WiFi calling works exactly the same as cellular calling on your phone. The only difference is that your call is connected via WiFi instead of your carrier's cellular network. There is no difference how the calls are made and received. There is no need to install or use any special apps. My phone switches automatically and seamlessly midcall from cellular to WiFi when I am in a weak cellular reception area.
All of the Apps listed by
Doug (plus AT&T old Wifi App) also use WiFi to make calls instead of cell towers, hence the confusion when you use a generic term. @:-)
In practice I - and many others - have disconnected the "wifi" option for mobile calls due to the well known battery drain, as summarized by T-Mobile:
1.On LTE radio only battery drain is about 0.3% to 0.7% per hour with no active use of the phone.
2.On turning on WiFi battery drain goes to 10% to 11% per hour with no active use of the phone.
3.On turning on Airplane mode to shut down LTE, followed by turning on WiFi, usage is still 10% to 11% per hour.
Really there is no need to enable WiFi calling in the USA if (1) You have an unlimited minutes plan (vast majority of us do) and (2) You are rarely outside of an area with sufficient cell tower coverage. Even so you could still use one of the apps listed above just as easily from a location that has wifi.
As I noted above, the bigger draw is when traveling overseas so as to avoid heinous roaming charges on the regular mobile networks. But again, the apps serve the same purpose. The only difference with enabling the wifi calling is that you phone can automatically toggle between cell towers and wifi, but then you risk high fees on the mobile network (or limit yourself to the same wifi locations that you could access through the apps).