The use of smart phones has changed the lifestyle of the society. Almost all kind of useful tools you can find on your smart phone. People used to buy goods every day. And for the purchase of goods they must pay. Security is very important while payment is concern. In this thesis we have designed and demonstrated a mobile phone application that can be used for a small shop or a big market. For any kind of commerce application, three different kind of entities are mostly involved: the customer, the sales person, and the management of the shop. Our designed mobile application has three different interfaces for three different kind of users: Manager Interface, Employee Interface, and Customer Interface. An interface for the system administrator is also designed, which should be used as an desktop application on the point of sale server. This application is flexible with capabilities of different payment options. Our proposed design can be implemented in any smart phone environment for example Android, iOS or Windows phone. This design provides availability, confidentiality, and integrity of payment data.