Investigate Issues with Data Sources –
the Data Source Tools

The Data Source Tools allow you to perform some basic investigations into connections to ADO Database, Web API and Web Service Data Sources from within App Studio without having to resort to more complex tools.

For ADO Databases you can execute SQL queries in order to verify the data contained within a database, for Web APIs you can send a Request to the Web API and check the Response and for Web Services you can run Web Service Transactions to check data returned.