Fieldwatch

Fieldwatch is a passive Android application for observing nearby Wi-Fi access points and Bluetooth Low Energy advertisements. It only listens to radio information exposed by the phone and does not transmit probes or require external radio hardware. All core data stays on the device, with no Fieldwatch account, advertising network, or backend server. Flexible views and filtering tools help users reduce large radio lists to the signals relevant to a field survey. An extensible signature catalog can classify recognizable radio sources and be updated independently. Reports, logs, sharing tools, and optional location tagging help document what was observed over time. The project emphasizes that classifications and co-travel patterns are hypotheses rather than proof of device identity or location.