This document describes a proposed mobile application for Windows Phone 7 that calculates download and upload speed to test network efficiency. It would allow users to input a file name and see how download speed varies over time, then displays the average speed. The application has modules for input, internet connectivity checking, speed calculation, and recalculation. It is designed to overcome limitations of existing desktop bandwidth tester applications by working on mobile phones and providing more detailed speed information. Hardware requirements include Windows 7 or mobile emulator, and the application would be developed using Silverlight and XNA framework.