Also with the Queclink GL500N GPS tracker you can set up SMS alerts to receive in a mobile phone when detect following: (geo fences, internal battery is low, movement detect, device power on). GL500N of Queclink apart from serving to Mobile Asset control is a good option for the GPS Container tracking. Queclink GL500N is it also a GPS Tracker with Microphone / Speaker that allows you to listen when making a call from an added phone to the allowed list. Another interest function that have the GPS tracker GL500N of Queclink is that allows firmware update or configuration change via OTA (Over the Air).