There are apps that decode via phone microphone, most of the stuff that fldigi and radios can do out of the box (for example, rtty) It works well, and is bi di

There are apps that decode via phone microphone, most of the stuff that fldigi and radios can do out of the box (for example, rtty) It works well, and is bi directional, you can key a transmitter and hold its microphone to your phone speaker and transmit valid "digital" modes. Works fine, especially over repeaters, which annoys the old folks and the lids alike.