Sync data between web server and mobile in android

I am making an application where all the data is stored in the server. When using application for the first time the data is downloaded in the SQLite form. Then if I use the application later the only time web services need to called is to check whether data is update in the server. If yes, the updated data will be added to the SQLite table and if no, the data will be fetched form the saved SQLite database in the memory. Any tutorials or code will help.