Mini GPS tracker is a multifunctional device that allows location, eavesdropping and Call-Back. It receives GSM and GPRS signal. This device determines the position based on the GSM network. By installing an active SIM card and a micro SD card inside, we can eavesdrop on and record sound from the vicinity of the device within 5-6 m. It is also possible to automatically make a call-back to a predetermined number if the sound intensity in the vicinity of the device exceeds 40 dB. Control is carried out by means of commands sent by SMS to the number of the SIM card, previously inserted into the locator (CARD NOT INCLUDED). The SIM card must be loaded with cash to be able to send return texts and make calls. Features of the GPS tracker activated by SMS code: 000 - acknowledgement of communication 102 - in response, we get a login and password to the map on the gpsui.pl website 444 - Device Activation/Reset 445 - Delete all microSD card memory 555 - Activate audio recording on micro SD card 666 - activation of the sound sensor (Call-Back), after detecting a sound above 40 dB, the locator will call back and when we answer we will hear what its microphone will pick up 777 - in response we get information about where the locator is located (street, house number, postal code, city, country), a link to a page with a map about this address, battery charge level 999 - activates the locator restart