The Sudoku Killer app is one that may just prompt you to make the switch. The user interface has been made to feel like you are doing the puzzle on paper and you can even take notes; in fact you're encouraged to take notes, right in the app.
You're given a note keypad and you can also choose more than one square at a time for fast and smooth notes. Your notes will be close as hand at they float right above the actual puzzle.
The app is free to use but you are only given 10 free puzzles. There are up to 800 available through in-app purchases of puzzle packs. Each pack is priced between $0.99 to $4.99.
The Sudoku Killer app is filled with all kinds of features that make it a fun option for players. The app features autosave so you never have to worry about losing your progress.
The progress gallery makes it possible to view all the puzzles you are currently working on to see how far you are in each, and the quick combination list button can really help save you time.
Additional features include the redo and undo buttons, the mini-calculator, the quick sum button, and a mistake highlighting feature. You can customize the experience by picking your color scheme you can go with the rainbow brights or the classic newspaper theme.
The app itself is constantly being tweaked behind the scenes to ensure stabilization and optimization.