Tablet - iOS - iPad 2
Put the summary of the bug you're having here
What I expected to happen was...:
Removal of a coal unit from pending fuel for iron processing.
What actually happened was...:
The game crashed, deleting my iron and current fuel.
Steps to Reproduce:
1. open furnace menu
2. Select an item to process
3. Select two fuel units
4. Remove one fuel unit
5. Reopen the game to see what was deleted when it crashed.