Since started playing with python pygame 2.0.0 dev8, have acquired the official Raspberry Pi Touch Screen.

interesting notes:

the dimensions of the touch screen closely match LEGO !

so that is my initial case:

Have python tk working, with buttons to call other shell scripts, so now have a camera app.

Still using the ac adapter, so not very portable, but the HQ camera +touch screen allows me to focus more dynamically.

With pygame 2, the touch screen allows me to zoom and rotate the images with my fingers after taking then. The screen is much lower resolution than the camera, so zooming out is required, otherwise you just get a corner of the image.

One interesting observation, the screen blanking function is blocked when I have a python window open, either tk or pygame, so I have to remember to close the app, if I want the screen to go blank.