Build an Andriod Application

Please see the below mentioned requirements before placing Bid. In this App you have to scan the QR code and encrypt that data with simplest Encryption Technique along with Current Location of the user and send that encrypted data to the web end.. Thanks Note : Must Understand the requirements..... No need to integrate Any payment gateway in the app so all you need is a button or password to confirm payment was made by cash to user of App.