Hello, unfortunately the app does not have such feature. To control what's on the TV, you'd have to use the physical remote that comes with the terminal. We have taken note of your feedback and forwarded it to the relevant team. Have a good evening!
+1 for channel changing with the phone. I used to be able to do this (and more) with the Illico app, but the Helix TV app is woefully inadequate. Looks like it was programmed over a summer internship.