I got an android TV stick (also have tried this on some other android TV systems) when I search on anddoid TV apps its a chore navigating the keyboard. The android TV remote app offers a keyboard which does absolutely nothing when you want to take advantage of your smartphone keyboard. It works wonderfully while in home screen. But that's it.
Android Remote app works fine in most of the apps. "Bluetooth Gamepad" app, "CetusPlay" apps are working to some extend.
Again, can't vouch for Off-brand Android TV sticks. Get Fire TV stick or Fire TV Box, if you are looking for remote app to control from Mobile instead of physical remote.
Roku also has mobile app for remote control.
I find if you click on the input field with the physical remote it will let you type with the phone app. Sometimes you have to tab over to it. If you type allot I would just get a small cheap bluetooth keyboard.
Are you looking for a keyboard that works with the DPad on ur android tv remote? Or not sure what your asking