According to the Particle Photon docs [1] it's actually capable of moving the mouse to absolute coordinates, but I haven't tried that yet.
[1] https://docs.particle.io/reference/device-os/firmware/#movet...
[1] https://docs.particle.io/reference/device-os/firmware/#movet...
There's a rewarding UX that can be made by switching the touchscreen to relative instead of absolute, you get more fine grained control.