Addition:
Unlike the other review state provides this app 8 different Sudoku variants and not just 3. He probably just the screenshots of Amazon Watch are probably outdated. Having found said the resemblance Andoku 2 the other, is probably alone in the colors of the playing fields. Otherwise, the app offers a lot more options and opportunities than Andoku. Also has Andoku (Andoku 2) no solution aids while they are pretty much perfect here.