>I need to write an application that can run on an Android device allowing data to be downloaded from a SQL Server 2012 database, updated on the device and then sent back to the SQL Server database.
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>Does anyone have any experience doing this and can recommend tools to use?


So the device is presumably wirelessly connected to your local network at the beginning of the day, and then the driver leaves and they are no longer connected?

Create a dynamic web page to get the required data and serve it as JSON.

The Android app can easily read the JSON, and store it in its own local database, a SQLite database to be precise (every Android App has its own SQLite database).