This GPS tracker have two tracking modes: SMS tracking and web platform tracking. For SMS tracking mode, you will need to use your smartphone to send command(refer to the manual) to the sim card that inserted into the GPS tracker. It will reply you the information by message. Text message fee will apply to your sim card. But no subscription required for this tracking mode. This GPS tracker also offer alternative tracking method - Web platform tracking. To enable the web platform tracking, please contact us after you purchase the item, we will create the account and pass the login details to you.