[Feature Request] Zoom on tap, play on second tap

[jopdorp]

For playability of 19x19 on mobile phones, especially in blitz and live games, it would be great if there was an option for "zoom" on tap.

Crazy Stone Deep Learning has a similar input mode.
The first tap just zooms in onto the board where the use tapped, then the board is draggable, if the user then taps outside of the board, the view zoom out to the full-board view, if the user taps the board, the stone is placed and then the view zooms out.