Create a group (smart of static) or perform an advanced search and view the results for your list of iPads and then do an "Export" to CSV and then choose "Applications" as the inventory item that you want to base your results on.
It will be a listing of all the Applications that are installed and on which devices they are currently installed on. Since it is a CSV file in excel, you can manipulate it any way you like (Pivot Table, Filters, etc).
Cheers!
Dan
