Idk, it seems like moving canvas up by the size of the screen keyboard is the simplest solution.
Mmm not sure that's the simplest solution. That would only work if you create the text at the bottom of the canvas, if you create it at the top then the text disappears too because it would get pushed outside of the screen... if anything, the solution would be centering the canvas to the text, taking into account the size of the keyboard and I'm not sure if that's an easy thing to do for all screen sizes, another issue that can appear from that is... what if you are editing the text? it would need to take into account font size, width/height of the text in the canvas, current zoom level... and probably more things.
I still think the easiest solution is adding a textarea field to the text panel, removing the need for the canvas moving around, zooming in/out, etc. so the keyboard doesn't cover it, geez, it would even allow us to use the pencil to handwrite the text
But yeah, let's see what the dev thinks ^^U