Screens for iOS 4.9.12 or later adds pointing devices support introduced in iPadOS 13.4. You can use a compatible mouse, trackpad or Magic Keyboard (to be released by Apple in May 2020) to control the remote computer Screens is connected to.
- Dragging (left-click and start dragging)
Please note that scrolling requires Magic Mouse 2, Magic Trackpad 2 or Magic Keyboard.
Unfortunately 3-finger gestures on Magic Trackpad 2 and Magic Keyboard are reserved by iPadOS but you can still trigger those via the device display.
For more details about iPadOS and pointing device support, visit https://support.apple.com/en-us/HT211008