Use tablet as touchpad when connected to big monitor/TV?

Instead of having to keep one's eyes on the tablet while clumsily
tapping around, why not turn the tablet into a touchpad when
mirroring the display of the tablet on a large screen? With that
setup, the tablet display wouldn't actually be mirrored, the big
display would look like a desktop computer display with a pointer
floating around on it. Also, the virtual touchpad on the tablet could
be resizable so that you could simultaneously show a virtual keyboard
(neither of which would show on the big display). Or there could be a
spot on the tablet display tapped to switch between virtual keyboard
and touchpad. Again, neither showing up on the big display.

I guess the current workaround is to plug pointing devices into the
touchpad. But why not an elegant software solution instead.




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LET ME KNOW IF I'M NOT BEING CLEAR. I AM NOT TALKING ABOUT SIMPLY
MIRRORING THE TABLET DISPLAY. ALSO NOT TALKING ABOUT USING THE TABLET
AS A TOUCHPAD FOR ANOTHER COMPUTER. THE ONLY HARDWARE INVOLVED IS THE
TABLET, A BIG DISPLAY (MONITOR OR TV), AND MAYBE A CABLE.

In the simplest of implementations...

The big display would mirror the tablet display. The tablet would
show a tiny pointer. How small doesn't matter because you won't be
looking at the tablet. The pointer location would correspond to
the current pointer location as shown by "developer options" on an
Android. That pointer would be driven by touch. That should be
easy enough, the only difference is that for tapping a relative
pointer position would be used instead of current tap position.

Apparently 99% of the programming for this stuff is already done
on Android tablets. Probably also on iPads or whatever. It would
just need a GUI switch and to make a few tiny adjustments when
connected to a monitor.

Being able to toggle to a virtual keyboard (without showing it on
the monitor) wouldn't be anything special, either.






Instead of having to keep one's eyes on the tablet while
clumsily tapping around, why not turn the tablet into a touchpad
when mirroring the display of the tablet on a large screen? With
that setup, the tablet display wouldn't actually be mirrored,
the big display would look like a desktop computer display with
a pointer floating around on it. Also, the virtual touchpad on
the tablet could be resizable so that you could simultaneously
show a virtual keyboard (neither of which would show on the big
display). Or there could be a spot on the tablet display tapped
to switch between virtual keyboard and touchpad. Again, neither
showing up on the big display.

I guess the current workaround is to plug pointing devices into
the touchpad. But why not an elegant software solution instead.