The document describes an e-wallet application that allows users to make payments using Near Field Communication (NFC) technology on Android smartphones. It discusses how the application works, including user registration and login, adding payment balances by activating vouchers, and making expenditures by scanning NFC tags on smart posters. The application transfers user and transaction data between the smartphone app and a web server for validation. The document also evaluates the application's performance and network usage, finding that data reception uses more bandwidth than transmission and that internet connectivity was the main constraint reported by users. It concludes by recommending a focus on security and expanding platform support for broader use.