YAAC ("Yet Another APRS Client") is an application for accessing the Automatic Packet Reporting System (APRS) amateur packet radio network (the network was originally invented by Bob Bruninga, WB4APR). YAAC functions as an end-node and digipeater for APRS datagrams when connected to an AX.25 Terminal-Node Controller (TNC) and radio transceiver. With YAAC, you can:
In receive-only mode, anyone can use YAAC. To transmit information over the APRS network, you must be a licensed amateur radio operator with privileges to transmit digital data in your country of residence.