Sudoku Of The Day

too many things wrong with interaction. for example, i need to click and hold on a number button to highlight the digit which makes it easy to misinput; it even punishs you for misinput; highlighting mode changes by itself with how long you hold the button so either you cant watch in the mode you want for long before it changes or you have to wait for seconds for the mode you want to appear; selection of a cell highlights all the row and column so its not immediate obvious which cell you just selected;