No, the mobile phone pays for stk SMS recharge, and users who have handled the package can charge the phone bill through STK menu. Stk can be understood as a set of commands for developing value-added services, a small programming language that allows SIM cards based on smart cards to run their own application software. Stk is a formal workshop protected by official website's certification laws. Stk technology is mainly used in mobile banking, stock trading, foreign exchange trading, financial secretary and other fields. This technology is used in new mobile services such as "mobile banking" and "stock inquiry and trading".