1. these GPS tracker can set sleep mode and time interval, please check its user manual . (sleep mode sms command is : SLEEP0000 5 , time interval sms command : 8090000 30) We provide free software platforms and apps, These settings can work well on our server. 2. i have sent our gps tracker protocol to you , If you use these gps tracker on your software platfrom, you could check the handshake of your server . 3. if you have any questions ,please feel free contact me . thanks