Adding app to apple TV 3rd gen
I'm looking to add an app to Apple TV 3rd gen. What's the process for that?
No process. It's not possible as the third generation Apple TV does not support apps. It only has server pushed channels. What you see on the screen is all that is available for it at this time.
If you need an App that does not offer a channel for a 3rd generation Apple TV, then you'll need to buy a newer Apple TV that does support Apps.