You know how sometimes in a show or a movie there is a character that has a "radio friend" that they talk to? Yeah that's what I want to do.

But I do not know how to so I came to ask you! Cheap, preferably.

Out of curiosity, I found this app on IzzyOnDroid, (which gave me the idea in the first place) Codec2Talkie that seems to be what I'm looking for but I'm unsure due to my ignorance.

A radio modem seems to be required as the app description dictates. I can find one somewhere no issue. But is this the correct approach? Is there a better way that I don't know of?