How to play ripped movie or home movie in iPad TV app

With the ability to either download or now direct connect to an iPad it’s easy to load a movie file. Is there a way to play such a movie with the Apple TV app? Where are the movies stored on the iPad that I’ve purchased through the app?

I use Waltr2 in conjunction with my Mac.

There are lots of free and pay iOS apps to play MKV and other files on the iPad. Here are two free ones: