I haven’t used it in a very long time but there was an RDP app on Android that kept the remote desktop session at 100%. This, of course, meant that the remote desktop was huge compared to the phone’s screen.
The way they handled navigation was by keeping the cursor in the center of the screen and letting you drag the session itself underneath the cursor.
You moved the desktop itself and not the mouse cursor.
I’d like to see this in RoyalTS. It would be useful for the grid view where multiple desktop sessions are shown at one time.