In one embodiment, a method includes collecting, by a magnetic navigation device, magnetic measurements of a particular geographical region in accordance with a position and trajectory of the magnetic navigation device; accessing a global navigation satellite system (GNSS) signal status and a network connection status on the magnetic navigation device; determining an operational mode for the magnetic navigation device based on the GNSS signal status and the network connection status; determining whether to transmit the magnetic measurements to a server or store the magnetic measurements locally on the magnetic navigation device based on the operational mode; and performing navigation or localization operations using the operational mode.