aprs.fi

aprs.fi gives packet radio a geographic memory. APRS stations heard by volunteer iGates appear on a live map with callsigns, position, course and recent path; fixed stations can contribute local weather, and digipeaters may publish battery voltage or other telemetry. A station page connects the latest packet to history graphs, raw frames, nearby stations and network diagnostics. That makes the service useful for following a mobile event, checking whether an iGate hears a tracker, or investigating how packets cross a local digipeater network.

The bright icons are not authenticated aircraft-style tracking. APRS permits accidental bad GPS fixes and deliberate impersonation, duplicate suppression hides some receiving paths, and packets may arrive late. Position history is public and may be retained or exported, so beaconing has a real privacy consequence. The official guide states these limits unusually plainly. Treat aprs.fi as an amateur network observatory and troubleshooting tool, not a safety-critical locator; within that role, its combination of maps, packets, weather and telemetry is exceptionally deep.