Comparison

NineGaps vs Rudoku

Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.

Head to head
About

NineGaps

This is a challenging puzzle game where you place numbers 1-9 into gaps, matching operations. It offers a unique twist on number puzzles with multiple difficulty levels and endless replayability.

Highlights
  • Unique puzzle gameplay
  • Cute graphics
  • 5 difficulty levels
  • Unlimited puzzles
  • Leaderboards and achievements
  • GameCenter integration
Features
Read full description

Featured by Apple as "Best Math Puzzle Game" and "New and Noteworthy" NineGaps is a highly addictive and tricky puzzle game. The goal of the game is really simple. You have to use your wits to place numbers from 1 to 9 in the missing gaps, while matching the operations presented in the puzzle. It's just like sudoku, but different! FEATURES: • simple and unique puzzle-based gameplay • cute graphics • 5 difficulty levels • unlimited brain burning puzzles • global and friend leaderboards • achievements • GameCenter integration • highly addictive and fun! Fans of Sudoku, KenKen and TwentyFour will feel right at home! Test your puzzle cracking skills with NineGaps today! PRESS REVIEWS: ..."sudoku-style puzzle game featuring a clever twist", Macworld ..."polished, fantastic looking iPhone app that anyone can enjoy", MacYourself ..."there is no reason this great puzzle app shouldn't be downloaded today", AppModo ..."with random boards the replayability is pretty much endless", In Touch Reviews ..."simple game with a simple design and does it simply perfect", GameZebo ..."make way for another highly addictive game coming out for your iPhone", Mobilewhack ..."great for all ages whether you want a math refresher or a fun way to teach kids math skills", The AppPodcast ..."this is a simple looking brain burning challenger", iPhone Footprint ..."sudoku meets calculator, has baby, calls it NineGaps", Mobile Game Faqs ..."highly addictive puzzle game", iPhone Toolbox ..."fun and challenging", AppChatter ..."easy to pick up and hard to put down", iPhone App Reviews CONTACT US - Visit us: ninegapsapp.com - Follow us: twitter.com/quadionTouch - Become a fan: facebook.com/pages/Quadion-Technologies/65161686424 Check out our other exciting games: Rune Trails and Wordweaver

About

Rudoku

This is a challenging number and logic puzzle game with multiple modes and difficulty levels. Track your progress with detailed stats and earn achievements. Enjoy endless playability with unique puzzles and accessibility features like dark mode.

Highlights
  • Multiple game modes
  • Adjustable difficulty levels
  • Variable board sizes
  • Detailed gameplay stats
  • Multiple achievements
  • Dark and light color modes
  • No in-app purchases
Features
Read full description

Rudoku is an expert level puzzle challenge for fans of numbers and logic games. Multiple game modes, difficulty levels, and board sizes will keep your brain stimulated as you decipher the solutions to each puzzle. Maintaining high gameplay stats and earning multiple achievements will make Rudoku your go-to brain teaser. Take your time and see how long it takes you in Relaxed Mode. Speed and accuracy come into play in Race Mode when your goal is to solve the puzzle before time runs out. Endless Mode makes each game board increasingly difficult to solve. KEY FEATURES • Endless Playability - Puzzles will never repeat while multiple game modes, difficulty levels, and board sizes keep the challenge fresh and your brain sharp. • Game Play Stats - In game stats will let you know the duration of each game, how many moves you made, your win percentage, and more. • Dark and Light Colour Modes - This great accessibility feature makes the screen easier on your eyes in the dark. • Multiple Achievements - Earn awards and Game Centre points a number of different ways including level achievements and stats challenges. • No In-App Purchases - Pay once and play. No need to waste time on ads or pesky in-app purchasing gimmicks.

Screenshots

NineGaps4 screens
Rudoku4 screens

Verdict

The call

The clearest difference is rating: Rudoku at 4.7 against NineGaps's 4.0. Rudoku also leads on monetization model (free vs paid) and update cadence (every 3 weeks vs every 26 months). NineGaps's advantage is iOS requirement (10.3 vs 18.0). On price, review sentiment, ratings volume and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Rudoku holds the better App Store score, 4.7 against 4.0. Both are backed by a comparable volume of ratings — 10 and 19 respectively. Written reviews complicate that: 88% of NineGaps's written reviews are positive against 85% of Rudoku's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

NineGaps ships an update every 26 months, Rudoku every 3 weeks. Both last shipped on October 29, 2026.

Scorecard4 real differences · 6 level
NineGaps versus Rudoku: the parameters behind the verdict, then further details
ParameterNineGapsRudoku
PriceFreeFree
Rating4.0 (10 ratings)4.7 (19 ratings) — better
Positive reviews88.1% of reviews — better84.6% of reviews
Number of ratings1019 — better
Update frequencyEvery 26 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPodiPhone, iPad
Requires iOS10.3 — better18.0
Further details — not scored
Size72 MB15 MB
Age rating4+4+
DeveloperQuadion Technologies LLCCerebral Gardens

Customer experience

NineGaps

All ratings11 ratings
Positive63.6%
Neutral27.3%
Negative9.1%
Written reviews109 reviews
Positive88.1%
Neutral8.3%
Negative3.7%

Rudoku

All ratings19 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews13 reviews
Positive84.6%
Neutral0.0%
Negative15.4%

Bugs and requests

NineGaps

Reported bugs

7 issues
  • Sound effects stop working intermittently
  • App crashes or fails to open on launch
  • Sound volume settings not saving between sessions
  • OpenFeint achievements not awarding properly
  • Mathematical calculation errors in some puzzles
Show 2 more
  • Unsolvable puzzle generation reported
  • Incorrect answer validation (marking correct answers as wrong)

Requested features

14 requests
  • Solution/reveal button to show answers when stuck
  • Hint system for difficult puzzles
  • Game auto-save functionality
  • Persistent sound settings across sessions
  • Global leaderboards for competition
Show 9 more
  • Multiplayer mode or WiFi challenges
  • Larger grids (4x4, 5x5) for increased difficulty
  • Puzzle numbering system for tracking progress
  • Ability to view completed games
  • Confirmation dialog before resetting high scores
  • Brackets/parentheses support in equations
  • Higher difficulty levels for advanced players
  • More game modes and variations
  • Improved color contrast for colorblind users

Rudoku

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

NineGaps

No in-app purchases

None

Rudoku

No in-app purchases

Questions

Is NineGaps free?
NineGaps is free to download, with no in-app purchases.
Is Rudoku free?
Rudoku is free to download, with no in-app purchases.
Which has better reviews, NineGaps or Rudoku?
Rudoku is rated higher. NineGaps averages 4.0 out of 5 from 10 ratings, while Rudoku averages 4.7 from 19 ratings.
Do NineGaps or Rudoku have ads?
Neither NineGaps nor Rudoku shows ads.
Which is updated more often, NineGaps or Rudoku?
NineGaps ships an update every 26 months, and Rudoku every 3 weeks. Most recently, NineGaps was updated on October 29, 2026 and Rudoku on October 29, 2026.

Other comparisons