Abstract: An electronic tag, e.g. for use as a tracker tag or combined tracker and data tag, with a cellular communication module is disclosed. The cellular communication module is configured to transmit an indication of a current geographical location to an external data server. The electronic tag can optionally receive tag data from an external tag reader and optionally comprises an output means configured to output the tag data. The tag's microprocessor is configured to switch off at least a transmitter part of the cellular communication module in response to first data contained in a Mode S signal of an aircraft transponder. Said transmitter part may be switched on again depending on data in signals from external source(s) as received in the tag.