This is the one you’re looking for – Jump Desktop (RDP, VNC, Fluid) Review

After getting my iPad I was disheartened to learn that sidecar wasn’t as fully featured as I hoped. While the picture was fantastic, it didn’t support an external mouse or the trackpad on the magic keyboard. So I started searching for remote desktop applications that would fit the bill of allowing me to access my desktop across the house with minimal effort. To my horror, I realized that almost none of them provided an easy way to resize my screen to fit the iPad resolution, further, when connected to an external monitor, they maintained the iPad 4:3 aspect ratio, which made for an unpleasant experience. Much to my surprise, this app not only automatically resizes the screen to the iPad resolution (when using their protocol and app), but it ALSO changes the video out resolution to fit whatever monitor you hook it up to. Absolutely incredible work! Well worth the money.
Review by hamiltongrp on Jump Desktop (RDP, VNC, Fluid).