As someone who does visual astronomy occasionally, I find it annoying to have to look away from the eyepiece and at my phone to tap the small RA/Dec slew buttons on the mount control, then look back in the eyepiece, then back to the phone, then back to the eyepiece etc...
It would be much better to allow the user to keep their thumb on the slew controls and simply slide around like a joystick so they move the mount while looking through the eyepiece, instead of having to tap small buttons individually.
