Tasky is a simple cross-platform todo/task application sample that allows you to track todo/task items. It illustrates proper application architecture layering and uses a common code base for the Business Layer, Data Access Layer, and Data Layer layers. It then separates out the User Interface and Application Layer into the appropriate device-applications.
The application runs on iOS, Android and Windows Phone 7 with a set of common classes shared across all three platforms. Open the TaskyMD_Mac.snl solution to see the iOS and Android apps on Mac OS-X and use the TaskyVS.sln with Visual Studio to see the Android and Windows Phone 7 apps.
Bryan Costanich, Craig Dunn