Comparison

Slitherlink vs Sumaddle

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

Head to head
About

Slitherlink

Solve logic puzzles by drawing a single loop around clues on a grid. Connect dots to form a continuous line, with no crossings or branches. Offers endless fun and intellectual challenge for puzzle enthusiasts.

Highlights
  • Draw a single continuous loop
  • Surround numbered clues
  • Pure logic, no math required
  • Weekly bonus puzzles
  • Multiple difficulty levels
  • Auto complete clues
  • Highlight link segment
Features
Read full description

Surround each clue with lines to form one single loop! Each puzzle consists of a rectangular lattice of dots with some clues in various places. The object is to connect the dots surrounding each clue so that the number of lines equals the value of the clue and the lines around all clues form one continuous loop with no crossings or branches. Empty squares may be surrounded by any number of lines. Slitherlink are addictive loop-forming puzzles which were invented in Japan. Using pure logic and requiring no math to solve, these fascinating puzzles offer endless fun and intellectual entertainment to puzzle fans of all skills and ages. The game features 2-finger tapping for quick zoom, auto complete clues setting and a link segment highlighting option to help to avoid creating separate loops. To help see the puzzle progress, graphic previews in the puzzle list show the progress of all puzzles in a volume as they are being solved. A Gallery view option provides these previews in a larger format. For more fun, Slitherlink contains no ads and includes a Weekly Bonus section providing an extra free puzzle each week. PUZZLE FEATURES • 200 free Slitherlink puzzles • Extra bonus puzzle published free each week • Multiple difficulty levels from very easy to extremely hard • Grid sizes up to 16x22 • Puzzle library continuously updates with new content • Manually selected, top quality puzzles • Unique solution for each puzzle • Hours of intellectual challenge and fun • Sharpens logic and improves cognitive skills GAMING FEATURES • No ads • Unlimited check puzzle • Unlimited Undo and Redo • Auto complete clues • Highlight link segment • Quick zoom using 2-finger tap • Concurrently playing and saving multiple puzzles • Puzzle filtering, sorting and archiving options • Dark Mode support • Graphic previews showing puzzles progress as they are being solved • Portrait and landscape screen support (iPad only) • Track puzzle solving times • Backup & restore puzzle progress to iCloud ABOUT Slitherlink have also become popular under other names such as Fences, Loop the Loop, Loopy, Suriza, Dotty Dilemma and Number Line. Similar to Sudoku, Kakuro and Hashi, the puzzles are solved using logic alone. All puzzles in this app are produced by Conceptis Ltd. - the leading supplier of logic puzzles to printed and electronic gaming media all over the world. On average, more than 20 million Conceptis puzzles are solved each day in newspapers, magazines, books and online as well as on smartphones and tablets across the world. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://www.conceptispuzzles.com/index.aspx?uri=info/doc/220

About

Sumaddle

This logic puzzle game transforms pencil-and-paper challenges into interactive brain teasers. Fit number combinations to clues using pure logic, with no mental arithmetic required. Enjoy over 150 free puzzles of varying difficulty, with built-in help and offline play.

Highlights
  • Interactive logic puzzles
  • Number combination fitting
  • Pure logic solving
  • Built-in help and mistake correction
  • Over 150 free puzzles
  • Offline play
  • Ad-free experience
Features
Read full description

• “Brilliant puzzle game”, UK App Store review Apr 2025 • “Best Puzzle Game I’ve Ever Played”, US App Store review Jan 2025 • “The ONLY iOS game I've never gotten tired of”, Reddit review Apr 2024 This type of logical puzzle was first seen in the Japan Puzzle Championship 2006 and is sometimes known as Doppelblock, or Smashed Sums. When played with pencil and paper, these puzzles can be hard work to solve. Sumaddle changes that by adding the essential element of interaction. This transforms the puzzles into intriguing brain teasers that unfold before your eyes. Each puzzle has a unique solution. Finding the solution involves fitting the number combinations to the clues. The app makes it easy to view the possible combinations, you don’t need to do any sums in your head. Instead, you can focus on using logic to narrow down the combinations and find a fitting arrangement. Some reasons why you will enjoy playing Sumaddle: • puzzles range in size and difficulty from small and simple to large and mind-blowing • more than 150 puzzles are included for free • all puzzles can be solved with pure logic, no mental arithmetic required • the sophisticated built-in help can explain the logical reasoning at each step and also fix mistakes if you go wrong • the built-in help is completely free, use it as much as you like • works offline (great for long journeys) • a high standard of accessibility, including comprehensive support for VoiceOver • ad-free play - there are absolutely no ads! IGRS age rating (Indonesia Game Rating System): 3+ Designed and developed in Winterthur, Switzerland

Screenshots

Slitherlink4 screens
Sumaddle3 screens

Verdict

The call

The clearest difference is update cadence: Sumaddle at every 3 weeks against Slitherlink's every 4 months. On price, rating, review sentiment and ratings volume 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. Slitherlink sells 13 one-off in-app purchases and Sumaddle sells 15 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for Slitherlink against 4.9 for Sumaddle. Both are backed by a comparable volume of ratings — 457 and 767 respectively. Written reviews are what separate them: 89% of Slitherlink's written reviews are positive against 95% of Sumaddle's.

UpkeepUpdate frequency

Slitherlink ships an update every 4 months, Sumaddle every 3 weeks. The most recent releases landed on September 27, 2026 and September 25, 2026 respectively.

Scorecard1 real difference · 9 level
Slitherlink versus Sumaddle: the parameters behind the verdict, then further details
ParameterSlitherlinkSumaddle
PriceFreeFree
Rating4.8 (457 ratings)4.9 (767 ratings) — better
Positive reviews89.5% of reviews94.9% of reviews — better
Number of ratings457767 — better
Update frequencyEvery 4 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better16.0
Further details — not scored
Size7 MB30 MB
Age rating4+4+
DeveloperConceptis Ltd.Jonathan Buchanan

Customer experience

Slitherlink

All ratings457 ratings
Positive96.5%
Neutral2.2%
Negative1.3%
Written reviews171 reviews
Positive89.5%
Neutral7.6%
Negative2.9%

Sumaddle

All ratings767 ratings
Positive98.3%
Neutral0.7%
Negative1.0%
Written reviews98 reviews
Positive94.9%
Neutral1.0%
Negative4.1%

User reviews

Slitherlink

From 457 App Store ratings

What we love

  • 🎉 Challenging and fun puzzles
  • 👍 Well-designed and intuitive interface
  • 🔍 Helpful check and undo features
  • 💡 Variety of puzzle sizes and difficulty levels
  • 🧠 Requires logical thinking

Room to improve

  • 🔍 Lack of coloring/marking tools to differentiate loop segments
  • 💰 Expensive puzzle pack prices
  • 🌙 No dark mode option
  • 🐛 Occasional bugs and crashes
  • 🔍 Limited free puzzle content

Sumaddle

From 767 App Store ratings

What we love

  • 👍 Fun and challenging game
  • 👍 Clean and intuitive interface
  • 👍 Helpful hint system
  • 🚀 No ads or data collection
  • 💡 Unique puzzle concept

Room to improve

  • 🐛 Automatic hints can be intrusive
  • 🐛 Inability to replay completed puzzles
  • 💡 Need more free/sample puzzles
  • 💡 Difficulty progression could be improved

Bugs and requests

Slitherlink

Reported bugs

3 issues
  • App not loading properly for some users
  • Freezing issues on login screen
  • Incompatibility with older devices

Requested features

5 requests
  • Add a dark mode option
  • Implement coloring/marking tools for loop segments
  • Provide more free puzzle content
  • Reduce pricing for puzzle packs
  • Add a rewind/undo feature to go back to previous puzzle states

Sumaddle

Reported bugs

2 issues
  • Losing progress when minimizing the app
  • Inconsistent difficulty ratings

Requested features

4 requests
  • Ability to selectively pencil in notes
  • More difficult puzzle options
  • Synced progress across devices
  • Detailed statistics and leaderboard

In-app purchases

13 purchases

Slitherlink

One-time13
  • Medium Snacks 1$0.99
  • Easy Variety 1$1.99
  • Easy Variety - Large 1$1.99
Show 10 more
  • Medium Variety 1$1.99
  • Medium Variety - Large 1$1.99
  • Hard Variety 1$1.99
  • Easy Variety 2$1.99
  • Medium Variety 2$1.99
  • Hard Variety 2$1.99
  • Big & Easy 1$1.99
  • Big & Medium 1$1.99
  • Hard Variety - Large 1$1.99
  • Big & Tough 1$1.99
15 purchases

Sumaddle

One-time15
  • Quirky, Pack 5$0.99
  • Very Difficult Puzzles$0.99
  • Quirky, Pack 1$0.99
Show 12 more
  • Premium 9x9 Puzzles, Pack 1$0.99
  • Crafty, Pack 1$0.99
  • Crafty, Pack 2$0.99
  • Crafty, Pack 3$0.99
  • Sneaky, Pack 1$0.99
  • Sneaky, Pack 2$0.99
  • Sneaky, Pack 3$0.99
  • Tricky, Pack 1$0.99
  • Tricky, Pack 2$0.99
  • Tricky, Pack 3$0.99
  • Assorted Puzzles$0.99
  • Puzzle Generator$9.99

Questions

Is Slitherlink free?
Slitherlink is free to download, with in-app purchases available.
Is Sumaddle free?
Sumaddle is free to download, with in-app purchases available.
Which has better reviews, Slitherlink or Sumaddle?
Sumaddle is rated higher. Slitherlink averages 4.8 out of 5 from 457 ratings, while Sumaddle averages 4.9 from 767 ratings.
Do Slitherlink or Sumaddle have ads?
Neither Slitherlink nor Sumaddle shows ads.
Which is updated more often, Slitherlink or Sumaddle?
Slitherlink ships an update every 4 months, and Sumaddle every 3 weeks. Most recently, Slitherlink was updated on September 27, 2026 and Sumaddle on September 25, 2026.

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