You can install the Roku app from the Android Play Store to your Android device. It provides a number of Roku functions including remote control ability and a Roku channel selection screen. With that you can also view programming from THE ROKU CHANNEL, whether it is currently being displayed via your Roku device or not. What it doesn't do is give you the capability of the displaying any channel other than The Roku Channel.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Do not ask me support questions via private message -- post them publicly to the Community where others may benefit as well.
If this post solves your problem please help others find this answer by clicking "Accept as Solution.". Please only do this if it ACTUALLY solves your problem.
Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600