GSM modem can be used for various applications, e.g. CSD, USSD, STK, SMS, GPRS, Fax, etc.

If the modem is used for SMS application and comes with MOBITEK SMS Gateway Development Kit, then we call or market it as SMS Modem.

If the modem is used for STK application and comes with MOBITEK STK API, then we call or market it as STK Modem.