OneSource Communicator Lite
Communicator Lite is a free, general purpose, Push-to-Talk (PTT) application. Perfect for any group of people that works together as a team, especially healthcare professionals. Communicator Lite transforms a team’s smartphones into a PTT Walkie-Talkie for use with free live voice over any network or Wi-Fi connection.
When seconds count there is an Emergency PTT button which when activated, will alert all designated users, even if the app has been terminated.