In the MCPE 1.2 beta, I attempted to shift-click an item into my inventory and it caused my game to crash. I reopened the world and tried again and it crashed again.
To replicate: Open your inventory, hover over an item, hold down the shift key, and left-click the item.
IMPORTANT: This issue is for the MCPE 1.2 beta ONLY.
Please do not mark unreleased versions as affected.
You don't have access to them yet.