* Should I change some specific settings on the TV to use the app?
Not really. You just need to put the TV in the regular "TV viewing" mode or one of the HDMI ports if you use a box for TV viewing.
Please keep it in mind that DON'T put the TV's source on screen mirroring mode (for Samsung TV, LG TV, and Roku devices). This is because putting the TV on screen mirroring mode would interfere with the app.