The Roku app's primary intended function is that of a remote control for the Roku. The only program content you can view on a mobile device via the Roku app is from Roku's own The Roku Channel for which they own the distribution rights.
Additional channel subscriptions you may have through Roku that you view through The Roku Channel generally only grant Roku the right to stream to Roku devices, not to mobile devices, and so can't be viewed through the Roku app.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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