This app is used to insert socket head cap screws, flat head cap screws, shoulder screws, and button head screws into your assembly. 

A command called 'Multi Quick Joints' is included to quickly add joints if you have added numerous screws and want to join them to say points in a sketch for locating them.

Another command called 'Multi Cut Bodies' is included to cut the holes required for the screws quickly.

The video gives a quick explanation about using this app.