The Adobe Creative Cloud for mobile approach seems to be to divide the functionality into individual apps, so there's an app that just builds brushes, there's this version of illustrator for folk who want some perspectives, supported by a wealth of grids, and viewing tools, and the neat template/ruler thing, which allows you to pick shapes to use as pen guides.
The app is designed to be used with the adobe stylus (and slide guide) which I think is there as a palm rest? further esearch required.
Zoom works reasonably well, though as per usual sometimes it thinks you are trying to draw a line, leading to additional undoing...the two finger left swipe to undo does work well, and didn't miss a beat.
The lack of fill tool is a bit of a pain, as is the lack of layers... there's a sort of layer thing, but it is really there to allow photos to be used for tracing, it has a level of opacity, but doesn't allow say a background tone to be layed down with a marker, and then have something drawn over the top... unless to draw your background elsewhere.
It could well be that the workflow is to do some tasks in the sister app "Adobe Illustrator Draw".. I'll try that tomorrow.
Sketch challenge for the day was draw a computer...