Environment Application Count Dashboard

Our users are wanting to know how many applications are in each environment, then show the applications under each environment by clicking on the environment, plus the ability to enter a comment next to the application.

Similar to the Cloud Admin Tool, Applications on top, user would click the environment, the grid would then show the applications. A text field next to the application name where they could input a comment.

Any thoughts on how this could be done? Appreciate it in advance!