ISS data-decode using iPhone

I have installed an "App" called Packet Pad in my iPhone.
It can decode audio AX.25(UHF) formatted data packets at 1200 baud.
Audio is acoustically coupled from a radio receiver into the iPhone.
Graphic shows some successfull decodes of ISS downlink digipeated 437.55MHz signals
received whilst ISS orbiting over Perth.
Now, portability is possible as radio and iPhone both run on batteries!

Alternativley audio can be directly coupled from the radio to the iPhone using the circuit as shown.