Zello like Walkie Talkie. Is anybody working on this?

Summary
Zello is an interesting app to provide worldwide walkie talkie however security is questionable.
Using Freedombox on a small piece of battery operated equipment with push to talk headset compatibility, establish a communication link to a studio from a (several) field citizen journalist(s). The device would be small and will probably WiFi tether off a journalist cell phone. The reason this device works independently from the journalist apps is to provide a connection without running the full streaming software.

The device would need to have the preprogrammed capability to boot into a default configuration with little or no user interaction.

The power to this should be 5V USB.

Problem
The summary explains the problem, the project platform needs to be determined. Looking for people with experience interested in developing this.

If somebody or somebodies want to take this idea on for development (I can help there, however, my experience in freedombox internals is limited.

Solution
Yet to be defined

Screenshots/Layouts
Yet to be created

Alternatives
Yet to be discussed

Tasks
Yet to be determined.

Rethink this above Buildroot, OpenWrt or similar.

The Zello on-premise server has a 1 time license fee per server.