Location Based Service (Lbs); Voice Monitor - GPS Tracker GSM/GPRS/ User Manual

6.12.2 After configure the APN, send "address+password" to device, it will
reply SMS including real street/address name. For example: No.113,
Guankou 2nd Rd, Nantou, Nanshan district, Shenzhen, Guangdong,
china.

6.13 Location based service (LBS)

When the tracker device doesn't receive valid GPS signals, tracker will
positioning by location based service(LBS), the messages includes the GPS
coordinates of the last position in SMS mode, but the LAC in message is the
current new position, the location can be seen by input the LAC code in the
menu "Manual Track" of web platform www.gpstrackerxy.com, you can also
send command "address+password" to tracker to get the newest absolute
address and GPS coordinates as well; tracker will automatically switch to track
by location based service in GPRS mode, and actualized on the map of web
server with LBS mark. And there may be some inaccuracy with actual location
by LBS tracking; the bias depends on GSM reception.
Note: This feature can be used normally in most areas according to the signal of
GSM network. It may not be available in some areas.

6.14. Voice Monitor

The command to switch between Track and Monitor mode are "tracker"
6.14.1
and "monitor".
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