Zello is an application for your Android phone with which you can use it like a walkie-talkie, very useful for sites with low coverage, the program is absolutely free and only consumes Mbps of data rate or if you in a WI-FI network cost will be 0 and consumed Mbs data rate of your cost will also be 0.
Zello is a free application that converts tuSmartphone or PC into a walkie-talkie. The application only requires internet access to function.
Usage is very easy, thanks to the simple home screen that has the program, simply press a button to talk and you’re informed, and best of all, the service is totally free! Also works with contact worldwide. With Zello can create public channels, or simply chat with a friend privately. To add the contacts you search your name or email list and just the other person accepts the application and you are in a direct line.