□ Main function- Payment: credit card, gift card, payOn postpaid transportation card, cash card, app card payment function- Transaction history inquiry: Transaction history inquiry function by date and payment type, receipt sending function by SMS text message and e-mail- Card reader linkage: reader Bluetooth connection function, reader integrity check function- POS app linkage: Provides payment function in conjunction with other apps□ Service environment- Android 4.4 or higherㅁ Required access rights- Phone: Running security program (VGuard)- Device location: Scan and connect to nearby Bluetooth readers- System notification: User notification when a malicious program is detectedㅁ Selective access rights- Camera: Scan barcodes and QR codes