The aim of this paper is to combine WebService technology with android platform technology to develop application update system. In this update system, the Android application would interact with WebService server to get information of whether to upgrade, and display related information returned from WebService on the android device. This article consists of two parts: WebService and android application client. WebService checks the version and compares to determine whether to update this APP; Android client is responsible for downloading, installing and displaying progress bar for updating. This article also shows Handler asynchronous processing for UI updating display and Ksoap2 android open source library to parse WebService data. As the result, this solution is proved a reliable and practical way to download and update through internet after testing on different Android terminals.
