Tableau integration with Civicrm
I use Tableau to enhance the reporting possibilities of CiviCRM.

Tableau can connect to many different data sources. I use a SQL connection to this, and this gives me full access to all the data tables in CiviCRM. I can then use Tableau to make interesting connections between different tables in an easy way.

I have not explored API connection, but I think that would be just as possible as SQL connection.