In Mini Number Place 6x6 #2, user specifies a cell first and then specifies a number to input or remove. If user mis-touched the cell because of small screen, user can modify the place by swiping. But there is no way to modify mis-input of number buttons. Please use undo and re-push the button.
"Mini Number Place 6x6 #2" has small-sized board, but it is so-so difficult. It will need solving techniques called 'Locked Candidate', 'Naked Pair', 'Naked Triple', 'Hidden Pair' and 'X-Wing'. In the Application, 'Tuple' means Naked or Hidden pair.