A wearable device, e.g., a smart watch, may be connected to a communication device, such as a mobile smart phone, via Bluetooth or other Near Field Communication (NFC). In particular, the wearable device may have a touch screen that may serve as an extended display and/or user input device of the communication device. For example, a user may receive payment related notifications on the wearable device. The user also may operate the wearable device to make and/or receive payments, view transaction history, view and/or accept offers from nearby merchants, view and/or check in to nearby stores and etc. Further, the wearable device also may allow the user to make payment transactions in extreme environments not suitable for the communication device, such as under water.