As the greatest potential growth area in the mobile industry, NFC (Near-Field-Communications) applications have attracted everyone’s attention. The emergence of “M-Wallet” is such an example. It is designed to utilize the convenience, portability and mobility of mobile phones to integrate all types of cards in the wallet into SIM/ Mobile handsets, so as to remove the need for users to carry all these cards. duoPass is a SIM based solution that Taisys developed to meet such market demands. duoPass serves as standard SIM. Thanks to technology, duoPass can carry another SIM sized dual-interface card to work jointly with mobile handsets and to perform contactless functionalities, such as membership management, credit check, mobile payment etc. The carried cards can be banking cards, even credit cards if they are issued by banks. This unique dual-card mode creates a new business model for solutions such as “M-Wallet”. It resolves the dispute between mobile operators and banks over the control of payment method. This solution can be used in the current mobile environment as it is compatible with existing mobile phones.