What does STK mean?
SIM Application Toolkit
Software tools SIM card, usually it as the STK will be remembered. A standard of the GSM is SIM card, means it can Service various value-added services telecom. This software includes a series of processes from pre-programmed, that is, how to, and how to engage the SIM card with the outside world, specifies and orders independent of the handset and the network begins. To mediate this tool SIM card to be able to create communicative, interactive, network, and user to access and control the network. Also, by means of which the SIM card is able to execute the orders to display menus, or get commands from the user in the phone display.