It basically allows you to make phone calls over the internet instead of relying on traditional phone lines, often for free.

Yes, you really can make free phone calls using the internet. The apps I'll mention come in two types: Some only work if the other person has the same app, while others let you call any number ...

and how to receive FaceTime calls if you use an Android phone. FaceTime: How to video chat on Android or a PC Like with any ...