# Killer Sudoku + > Logic puzzle game combining Sudoku rules with cage sum challenges. (iPhone/iPad app by James Gibbs.) - Source: https://appshunter.io/ios/app/killer-sudoku-plus/id866856408 (this page in markdown: same URL + `.md`) - Developer: [James Gibbs](https://appshunter.io/developer/866856411) - Category: Games, Puzzle - Price: Free with in-app purchases - Rating: 4.76/5 from 299 App Store ratings · 63 written reviews indexed - Age rating: 4+ - Requires: iOS 12.0 · 2 MB - Languages: English - Released: 2014-10-25 - Data updated: 2026-08-22 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/killer-sudoku-plus/id866856408/reviews.md ## What is Killer Sudoku +? Killer Sudoku is a fun and challenging variant of Sudoku. If you love Sudoku, why not give Killer Sudoku a try? As with Sudoku, the objective of Killer Sudoku is to fill the grid with the numbers 1 to 9 such that each row, column and nonet (3x3 group of cells) contains each number only once. In addition, a Killer Sudoku grid is divided into cages, shown with dashed lines. The top-left corner of each cage shows the sum of the numbers within it. The same number cannot appear more than once in a cage. There are ten puzzles included for free, and thousands available for download. The puzzles are graded into difficulty levels, all excellent quality and with a unique solution. The app and puzzles are from the maker of https://www.dailykillersudoku.com. ## Key features - Sudoku variant gameplay - Cage sum challenges - Unique solution puzzles - Graded difficulty levels - Thousands of puzzles available ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | 100 Easy Killer Sudokus #1 | $0.99 | one-time | | 100 Moderate Killer Sudokus #1 | $0.99 | one-time | | 100 Hard Killer Sudokus #1 | $0.99 | one-time | | 100 Extreme Killer Sudokus #1 | $0.99 | one-time | | 100 Mixed Killer Sudokus #1 | $0.99 | one-time | | 100 Easy Killer Sudokus #2 | $0.99 | one-time | | 100 Hard Killer Sudokus #2 | $0.99 | one-time | | 100 Mixed Killer Sudokus #2 | $0.99 | one-time | | 100 Moderate Killer Sudokus #2 | $0.99 | one-time | | 100 Easy Killer Sudokus #3 | $0.99 | one-time | | 100 Moderate Killer Sudokus #3 | $0.99 | one-time | | 100 Hard Killer Sudokus #3 | $0.99 | one-time | | 100 Mixed Killer Sudokus #3 | $0.99 | one-time | | 100 Extreme Killer Sudokus #2 | $0.99 | one-time | | 100 Extreme Killer Sudokus #4 | $0.99 | one-time | | 500 Extreme Killer Sudokus | $3.99 | one-time | | 100 Extreme Killer Sudokus #3 | $0.99 | one-time | | 500 Easy Killer Sudokus | $3.99 | one-time | | 500 Hard Killer Sudokus | $3.99 | one-time | | 500 Moderate Killer Sudokus | $3.99 | one-time | ## What do users think of Killer Sudoku +? Overall sentiment: positive **Pros** - 👍 Great game/app - 🧠 Challenging puzzles - 💡 User-friendly interface (once used to) - 💰 Good value for money/affordable - 🚫 No ads - ✅ Well-designed - 🔒 No tracking/privacy respected - 💯 High quality puzzles - offline Playable offline - 💪 Improves math skills - 🧩 Variety of puzzle packs - ✨ Many useful tools/features **Cons** - 🤔 Puzzles can vary in difficulty - 💰 Limited free puzzles - 🐛 Some puzzles have multiple solutions - 📱 Purchase restoration issues - 🖱️ Uncomfortable/confusing controls - 🔄 Undo functionality issues - 🛒 Download issues for extra puzzles **Commonly reported bugs** - Purchased packs disappear after factory reset/device change - Cannot download extra games, error message - Puzzles with multiple solutions - App jams after purchasing puzzles - App frozen/won't open - Pencil marks not working correctly - First screen is payment portal - App requires constant scrolling due to hidden menu **Most requested features** - Colorize squares individually - Left-handed option - Highlight all cells with a particular number - Highlight undone actions - Ability to undo undone actions - Game statistics (completion times, hints, errors) - Sort games by completion time - Remember timer setting between games - Turn off Undo including cage combinations - Hardware keyboard entry option for external keyboards - Android version - Doodle option for workings/sums - Pause button - Highlight duplicate numbers - Remove number from notes of influenced cells automatically - Clear button to remove all pencil marks - Calculator for sums - Add numbers into multiple squares at once - Hint feature that points to solvable square instead of solving - Rainbow coloring for cages - Tutorials/tips (e.g., 45 rule) ## Recent user reviews (10 of 63) All indexed reviews: https://appshunter.io/ios/app/killer-sudoku-plus/id866856408/reviews.md ### 5/5 — Great *2026-07-04, version 1.5.3* Love this App. Possibly one of my most used. Simple clean no adverts. Possibly need a new pack but happy going back through the ones I’ve done ### 5/5 — Best I’ve found *2026-06-28, version 1.5.3* Quality puzzles, intuitive gameplay and doesn’t try to upsell you constantly. Therefore the only place I do killer sudoku. For reference I only do the toughest puzzles (not always successfully!) ### 5/5 — Best Killer Sudoku App on the iPad *2026-05-28, version 1.5.3* This is actually an app version of my favorite Killer Sudoku website. Most of the same features that make that the greatest website are present here, too, including: 1. Unique solutions every time! 2. Puzzle packs available for purchase at every level, including my level, the highest one, Extreme. 3. Most puzzles I've purchased are symmetrical, which is my preference. An exception is 100 Extreme Killer Sudokus #2. 4. The timer can be turned off. I never want my Killer Sudokus timed! 5. Pencil marks available, using the same keyboard. 6. An ability to check what's been entered, looking at the whole board. Unlike some other Killer Sudoku apps, it does not show in red a number that can't be correct based on what has already been entered, which I consider to be very distracting, even though some may consider it helpful. 7. The ability to toggle between showing the numbers in entry sequence or number sequence. Although I have given this one a 5-star rating, there is still room for improvements, mainly along the lines of settings that are present in the web version but not here: 1. Remember that the timer has been turned off between games. 2. Turn off "Undo includes cage combinations". In other words, if I am using undo, especially several steps' worth, I don't want my cage combinations reset. 3. If playing on an iPad with a Bluetooth external keyboard, an option to use hardware keyboard entry instead of the app-specific onscreen keyboard. And one more request - Can we please have a version for Android? I have both an iPad and an Android phone, and I'd love to play this on both devices. ### 4/5 — Pretty great, needs one more feature *2026-01-01, version 1.5.3* Love this game and the user interface is very fast and intuitive once you get used to it. It would have been 5 stars+ if it had the ability to colorize squares individually ### 5/5 — Ni-ice *2025-04-02, version 1.5.3* But want iPad version to have a left handed option! Haha ### 5/5 — Hard :) *2025-03-10, version 1.5.3* Definitely the hardest killer sudokus I've found so far in an app. Really have to use your brain and maths skills on this one. You only get 10 puzzles free then you have to buy packs, though 100 for £0.99 isn't bad. It's the same format as the Daily Killer Sudoku website which are all free. ### 5/5 — I really love this app! *2024-12-12, version 1.5.3* I use it every single day. It’s massively improved my maths skills, and it keeps my thinking fresh, whilst at the same time providing a perfect retreat. Thank you. One small thing.i have bought multiple packs from you - but having just had to reset to factory settings after getting my charger port replaced, they have all disappeared when i restored my ioad. Hiw do I retrieve my packs please? ### 5/5 — Great sudoku app with no tracking! *2024-01-28, version 1.5.3* I downloaded this app because it doesn’t track me or share my data. After playing the free puzzles for a while, I paid for a bundle of new puzzles because I really like the app. For me, this has everything I need from sudoku, with the right level of easy/hard and a range of options, all of which can be turned off or ignored so I can play how I want to. As someone with dyscalculia this is really appreciated. You can start each puzzle with no help at all, no “starter” cells filled in, or I can fill in some cells one by one until I am able to get started. This works even with easy puzzles. It’s a level of control over each puzzle I haven’t seen in other apps. The only thing missing for me that I’ve seen in other sudoku apps is the option to highlight all cells filled in with a particular number. As someone who struggles with numbers, especially with seeing all the same numbers, I’ve found that a really useful feature. But I get that most people aren’t like me! Thank you to the developer for respecting my data privacy. ### 5/5 — Variations *2024-01-22, version 1.5.3* I enjoy the problems, however, I do find that problems, which are supposed to be of similar difficulty, can take from as little as 30 minutes to over 1.5 hours, a small number never being finished but abandoned. I can spend/waste a lot of time every day on them! ### 4/5 — Suggestion *2023-07-28, version 1.5.3* When you undo something or many things it is hard to find what was undone - I would like to see highlighting added to what was undone or even just allow to undo the undone. It would be nice to highlight different colors (9 colors) however the players wanted to use highlights ## Frequently asked questions about Killer Sudoku + ### What is Killer Sudoku? Killer Sudoku is a logic puzzle game that combines the rules of Sudoku with an additional constraint. In addition to ensuring each row, column, and 3x3 block contains numbers 1-9 uniquely, you must also ensure that numbers within designated "cages" sum up to the target number shown in the cage's corner, without repeating any number within that cage. ### How many puzzles are included? The app includes ten puzzles for free to get you started. Beyond these initial puzzles, there are thousands more available for download, offering extensive gameplay. ### Are the puzzles difficult? Yes, the puzzles are graded into difficulty levels, catering to a range of player skills. All puzzles are of excellent quality and are guaranteed to have a unique solution. ### Is this app free to play? The app itself is free to download and play, and it comes with ten free puzzles. Additional puzzles can be acquired through in-app purchases, offering a freemium model. ### What devices is this app compatible with? While specific device compatibility is not detailed in the description, it is a mobile application, suggesting it is designed for smartphones and tablets running common mobile operating systems. ## Version history (last 5 releases) ### 1.5.3 — 2020-12-30 Fixes a bug that can prevent puzzles from being downloaded. ### 1.5.2 — 2020-11-24 Bug fixes. ### 1.5.1 — 2020-11-23 Bug fixes. ### 1.5 — 2019-10-15 Enhancements and bug fixes in this version: - Updates to support iPhone 11 and iOS 13 - Enhancements to multi-cell editing - if multiple cells would gain the same final answer, add it as a pencil mark/note instead - If a cell contains a single number with an underline or question mark, show the "pencil mark" button instead of the "cancel" button - Updates to usage tips ### 1.4 — 2017-07-25 This version is packed with new features, and a few bug fixes, including: - Multi-cell selection: multiple cells can now be selected and updated together - Automatic sum: highlight multiple complete cages and they will be summed automatically for you - FILL button: fill the selected cell(s) with all possible numbers based on each cell's cage - CLEAR button: clear the selected cell(s) - Long press (hold down) a number to enter it as a final answer and remove all other numbers from the selected cell - Option, on start-up, to return to the puzzle from your last session - Improved layout and clearer text/images on some devices - Undo now undoes Combinations tab toggles (fade in/fade out) as well as cell contents - Usage tips ## Apps similar to Killer Sudoku + | App | Rating | Price | Category | | --- | --- | --- | --- | | [Kropki Puzzle](https://appshunter.io/ios/app/kropki-puzzle/id1390431292) | 4.8 (49) | Free | Games | | [Kakuro u](https://appshunter.io/ios/app/kakuro-u/id306200861) | 4.6 (299) | Free | Games | | [Killer Sudoku Master-SumSudoku](https://appshunter.io/ios/app/killer-sudoku-master-sumsudoku/id6464051208) | 4.5 (10) | Free | Games | | [Killer Sudoku - Puzzle Games](https://appshunter.io/ios/app/killer-sudoku-puzzle-games/id1549645019) | 4.8 (6,164) | Free | Games | | [Sudoku - Soduko](https://appshunter.io/ios/app/sudoku-soduko/id1466592441) | 3.5 (4) | Free | Games | | [Futoshiki Puzzle Game](https://appshunter.io/ios/app/futoshiki-puzzle-game/id846765771) | 4.6 (455) | Free | Games | --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-22.*