It is a Bluetooth chatting app with 2 additional functions: file exchange and 2-way voice calls. You can exchange text messages, files and voice call without any internet, nor cell phone data service. It is direct between 2 android cell phones or tablets. It is free and secure communication service. It would be very helpful app in environments with no internet, nor cell signals. Voice calls are on a 2-way voice channel, just like phones. You push a button to set up and shut down a voice channel.