When entering notes into the giant sudoku puzzle, it's super glitchy. Anything along the sides may or may not actually be input into the square. It's super hard to see they're so small. It does have zoom but when entering notes, you go in and out to enter correctly. After I entered all notes, you go through inputting final numbers and realize half your notes either disappeared or didn't actual get entered. Given that's the only one I do, in deleting the app