Not Evil Sudoku

Not Evil Sudoku is a minimalist, offline, and totally ad-free sudoku app for iPhone with over 50,000 installs and 200+ 5-star reviews.

Built natively for iPhone and iPad with the sole aim of providing users with a joyful sudoku-solving experience.

A sudoku beginner? Move by Move validation in Settings can tell you whether a move is correct as you make it.

Why I Made Not Evil Sudoku

One fateful afternoon, I had the sudden urge to play sudoku. Naturally, I went to the App Store and downloaded a few of the top results.

I was shocked at how terrible the user experience was in most sudoku apps. There was a banner ad at the bottom (which I could live with), a video ad every few turns (absolutely evil) and an ad after every game.

So, I did what any self-respecting programmer would do: I made one myself :)

I’m not against ads in general, but so few apps seem to be willing to do them in moderation.

Features

  • Fully offline
  • Ad-free
  • Real-time move checking
  • Timer: Track your sudoku-solving speed. The timer can be hidden in Settings if time pressure isn’t your thing.
  • Difficulty Modes: Easy, Medium, Hard
  • Haptic Feedback
  • Notes: Users can keep track of all the candidates for a cell with two modes:
    • the default which supports up to 4 notes which is ideal for easy and medium puzzles
    • the expanded version which supports up to 9 notes (Settings → More Settings → Expanded Notes)
  • Auto-clear Notes: When a number is placed, all instances of that number in notes in the same row, column and grid are cleared.
  • Undo: Take back the last action.
  • Streak: Number of consecutive days in which you’ve solved a puzzle.
  • Best Time: The shortest amount of time it has taken you to solve a puzzle (separate for easy, medium and hard)
  • Charts (Pro):
    • Track your solve speed over time for each of the difficulties
    • See how many games of each difficulty you played
  • Highlighter: When the user taps a number, the app highlights all the places where that number appears, making solving much faster.
  • Game Controls: Start over or start a new game at any time
  • Daily Sudoku Reminder: Sends a notification at the time the user chooses. For those who like playing a daily puzzle and don’t want to lose their streak.
  • Display Modes: Supports light and dark modes as well as switching between them within the app.
  • Themes: Switch up the app theme to freshen up the experience. Some colors require Pro.
  • Fun Alternate App icons (Pro).
  • Unlimited puzzles (Pro)

Users can play a daily sudoku game for free while leveraging all the powerful features of the app. Unlimited games can be unlocked with a small one-time purchase (Pro). Pro supports family sharing.

Get Not Evil Sudoku on the App Store