If you’re reading this article, you probably already know that Sudoku is a one-screen puzzle game based upon a 9-by-9 grid that’s partially filled with numbers. The objective is to fill the empty spaces of the grid with single digit numbers so that the same digit does not appear twice on any horizontal or vertical line. Additionally, the same number should not appear twice in any of nine 3-by-3 mini grids on the screen.

The fifth-generation iPod had a total of one Sudoku game, Electronic Arts’ Sudoku/Num-Pre. When we went to compile a master list last week of every iPhone Sudoku game, we discovered that there were so many versions—17, collectively costing over $70—that we literally crashed our iPhone 3G trying to install them all at once. We published the list on July 22, and our goal was to give you reviews after we finished testing them. Then new titles and updates were released.
Today, we bring you this updated list of 23 different Sudoku titles, each rated based on the same criteria. Our top-ranked Sudoku games are ones that offered fully-functional renditions of the game, with impressive interfaces, bonus features, user customization, and pricing as of the time we tested them. The fewer of these features a given game had, the lower it rated. While updates to these games may well be released over time, and their features may change, we couldn’t wait around forever for bad or so-so titles to catch up with ones that were already good or great. Ultimately, the lesson for new developers is clear: make your game great before you release it, not afterwards. There are so many iPhone titles now, including impressive ones, that the only prayer weak versions have is as giveaway demo software; truly impressive games can be had for $4-$6, and there’s even a very good free option. Read on for the details.
ACTSudoku ($3) by Houdah Software is a straightforward, light-on-frills presentation of the game with three levels of difficulty and only one style of background and tile art. It contains a random board generator, and by default offers automatic markers to hint at which numbers remain possibilities; unusually, you can only disable the markers by leaving the application and changing settings in the iPhone or iPod touch’s main settings menu. ACTSudoku is also silent; you provide your own iPod mode audio. A state-saving mode lets you return to any game you’ve interrupted.
ACTSudoku is an average title. There is a professional simplicity in its presentation with the automatic markers on, enabling users to more easily see their options, and a pop-up window makes selection of those options very straightforward. However, there’s not much to the title beyond a standard game of Sudoku. iLounge Rating: C.
Big Bang Sudoku ($5) by Freeverse is also a very simple rendition of the game, opting to avoid cluttering the grid with number-adding overlays in favor of a bottom-of-screen list of numbers that can be shifted into either answer or possibility markers. Other than four difficulty settings, you are limited to turning off or displaying a wisecracking “Sun God” character, a timer, or incorrect moves. Except for simple sound effects, which can be turned off, the game is silent, so you have to provide your own music. The single biggest thrill of the title is a gently moving starfield background; it is just too expensive given how simple it is. iLounge Rating: C-.
Enjoy Sudoku ($4) by Jason Linhart has the look and feel of a simple Windows application, with comparatively primitive graphics, clicking sounds, and an interface that is more functional than fun. With 35,000 puzzles built in, the biggest frills in here are a feature that goes out to the Internet to grab a challenge of the day, multi-stage undo and redo features, a Create Puzzle/solver mode, and an automatic pencil marks mode that provides all the possible answers for you to work through and easily solve the puzzle. The pencil mark possibilities are, however, extremely busy on the screen, and the price is steep considering how much more you get from a game like Gameloft’s Platinum Solitaire. Overall, this rates in our D-for-demo category. iLounge Rating: D.
Game Pack Vol 1 – Sudoku, Wordfind and PictureFlip ($5) by On-Core actually provides three different games in a single application. In addition to a simple version of Sudoku, you also get Wordfind—a clone of the newspaper puzzle Wonderword—and PictureFlip, which takes photos from your collection and scrambles them into tiles that need to be shifted to re-form the original image. The silent Sudoku title has a static background with static tiles, a pop-up window to insert new numbers, and an annotate feature to let you make guess marks. Three levels of difficulty are included.
On the merits of its Sudoku title alone, Game Pack Vol 1 would be nothing to write home about. The pop-up window is distracting, the lack of audio is disappointing, and the overall effort that went into this part of the title is not worth the $5 asking price. However, the other two built-in games do add some value—Wordfind is actually better than the Sudoku title. This isn’t a wonderful piece of software overall, but it’s OK. iLounge Rating: C.
Kamicom Sudoku ($2) by Sans Pareil/Justin Kaleta has one major advantage over some of its competitors: it has changing backgrounds, which can be unlocked to serve as iPhone/iPod touch art, and the designer bothered to at least create a semi-interesting game board on top of them. Though it is a very simple Sudoku game, and lacks for pencil-style markings, it has three levels of difficulty, 20 different backgrounds to unlock through games, and the ability to save your current progress in all 20 of them at the same time. At the moment, due mostly to the lack of pencil markings, there isn’t enough here to rate Kamicom outside of our D-for-demo category, but the developer claims that updates will make the game better over time. We’ll see. iLounge Rating: D+.
We originally described Killer Sudoku ($5) by WhiteNile Systems as “the single most confusing Sudoku game we have tested,” but an update fixed the biggest issue—its initial inability to generate playable boards. Now Killer Sudoku actually includes the two promised modes, Classic Sudoku and Killer Sudoku, along with the ability to save and open games, and solve newspaper sudoku puzzles. The Killer mode includes on-board tallies that impose additional rules on certain two- or three-unit parts of the grid. As before, no audio is included, and the help system isn’t extremely helpful.
Better than it was in its initial revision, and undoubtably aided by the Killer Sudoku variant, this is still a pretty limited game in terms of interface, and doesn’t currently provide possibility/pencil markings. At $5, it remains amongst the most expensive Sudoku titles out there, but needs a lot of work before it’ll be worth paying for at that price. iLounge Rating: D+.
Mr. Sudoku ($5) by Ambrosia Software started out as one of the most expensive Sudoku titles out there, but wisely dropped its price by 50% to become more competitive. It’s definitely one of the more functionally interesting versions of Sudoku we’ve seen, with its own introductory voice and music, fading your iPod music out; Mr. Sudoku not only creates new games in four different difficulty levels, but also saves your progress in multiple games at once. The most interesting thing about the title, which features only one style of art and tiles, is that it switches between button-style number entry and a finger-based text entry system that works just fine if you draw the numbers as they’re expected to be drawn. It’s missing a possibility marking feature.
While we do like Mr. Sudoku’s general approach, the lack of pencil/possibility marking and music during the game take away from what otherwise could have been a really strong title. Better than most of the demo-caliber Sudoku titles, and worth showing off because of the finger input recognition, the game nonetheless doesn’t come close to what Platinum Sudoku offers for a lower price. It might be worth revisiting after an update or three. iLounge Rating: C-.
There’s no doubt that the best of the Sudoku titles is Gameloft’s Platinum Sudoku ($4), and the reason is simple: tons and tons of options. This professionally developed, beautiful-looking title lets you select from 16 different fonts, 14 different backgrounds, 6 different grids, and 11 different, actually background songs. Some of these items are available at the start, others are unlockable through continued play; game music can be turned on or off. Handwriting number recognition and a pad can be toggled between, various types of hints and draft markings are available, and there are all sorts of other extras—voice samples, male and female coaches, puzzle modes, a puzzle solving mode, and a hybrid Sudoku/crossword puzzle game called Kakuro.
Kakuro, which is accessed by scrolling down from the main menu, is like Killer Sudoku in that you’re given number tallies that must be met to properly fill the grid. There are hundreds of different Kakuro puzzles built in here, adding so much to the title’s continued play value that they could—had anyone known was Kakuro was—have served as a standalone game. Given that those puzzles are here, along with the best version of Sudoku we’ve yet seen, you’re actually getting three times as much as in EA’s Sudoku, at half the price. This sort of great value combined with great design is the very definition of a flat A rated game, and fully worthy of our high recommendation. Platinum Sudoku is notably only the second iPod/iPhone game ever to receive our flat A rating. iLounge Rating: A.
Satori Sudoku ($2) by Kevin Kozan is a plain, no frills version of the game. Your only options are a sliding difficulty scale that includes easy, normal, and hard positions, the ability to automatically disable entry number keys that can’t possibly be correct, and a highlight feature that lets you see whichever cells could match a given number you select. There is no audio; you provide it with your iPod. Though this isn’t an exciting rendition of the game, it’s competent, decently presented, and reasonably priced. We’d call it about average overall. iLounge Rating: C.
Sudoku ($8) by Electronic Arts is a remake of the same-named Click Wheel iPod Game, with identical features and artwork that has been reformatted to fit the iPhone/iPod touch screen. Though the transition screens and music have a wonderfully Japanese look and sound, there’s no customization a la the best other Sudoku titles we’ve seen. This one continues to offer a newspaper puzzle solver, easy mini markings for square possibilities, and an easy to understand interface.
Five levels of difficulty are included, the latter two unlockable, and an error checking mode can be turned on or off. You can also tap a button or shake the iPhone to show all of the possible options, a feature called Auto-Fill Helper. The music can be turned off, but you can’t play your iPod music during the game. Overall, this is a nice Sudoku game thanks to its Japanese theme, but Platinum Sudoku shows that you can do much better for half the price on the iPhone. iLounge Rating: B.
Sudoku ($3) by Mighty Mighty Good Games is another mostly no-frills take on the game. Its biggest feature is the ability to change the color scheme to one of ten plain combinations; four levels of difficulty are included, as are a fairly limited array of 200 puzzles. You can make an italic font note as to what you think a square might be, receive hints, and compete against the timer, but there aren’t sophisticated space markers or other options here. The game is silent and accepts iPod music. There’s also a free version of this app called Sudoku (Free) which has only three color swaps and doesn’t promise as many puzzles. Neither is great, but our advice would be to stick with the free one unless the $3 version becomes substantially better over time; both are demo-worthy, one charges you for that quality. iLounge Rating of Sudoku: D-. iLounge Rating of Sudoku (Free): C-.
Sudoku ($3) by Shekhar Yadav is a pretty bad take on the game, with the worst interface (tap 9 times for 9, use no markers), four bizarrely-named difficulty levels, and five fugue-like backgrounds. The grid is extremely plain and can’t be made easier to see unless you choose a less busy background. You provide your own music, and the game has no sound effects. We’d call this worse than a demo; it’s one of few games we’ve seen that we’d give an F overall for the sheer audacity of charging for something so harsh on the eyes and brain. iLounge Rating: F.
SudokuManiak ($1) by Alexandre Minard is a plain but cheap variant on the game. With the ability to save your previous stage of play, a daily downloadable web challenge, and six levels of difficulty, the game features possibility markings, an undo feature, and the ability to randomly generate puzzles. While the interface isn’t anything special, it’s not bad, and the game saves your past scores to a table. It’s a full game of Sudoku at a decent price. iLounge Rating: C.
Sudoku.MD ($4) by RightSprite is a complete standard game of Sudoku, including pencil marking, with a nice Japanese theme. Nowhere near as polished as Electronic Arts’ similarly Japanese-themed version of the game, it lacks audio and frills, but also sells for half the price. There’s not a lot here to do besides play a decent game at one of three difficulty levels. Right now, it’s an average title at its current price, but if it was cheaper or had more initially available depth, it might rate higher. iLounge Rating: C+.
Sudoku Pro by OutOfTheBit/Ignazio Motisi ($2) is another plain take on Sudoku with a fine but not great interface. Three levels of difficulty are available, and the game makes it easy to enter either your actual or potential number picks by clicking on a grid field and calling up a bottom-of-screen keyboard. Additional puzzles are automatically generated. Given the price, we’d call this a bit better than a demo, but it’s still below average overall. iLounge Rating: C-.
Phase2 Media offers two different games, Sudoku Unlimited ($3) and Sudoku Classic (Free), which differ only in frills. The Unlimited version has five difficulty settings, three different font-and-background combinations, and options for sound effects, animations, a timer, showing errors, and the like; an auto-fill feature shows you all the possibilities so that you can solve the puzzles more easily. A cool-looking Hint mode also provides answers if you need them. Phase2 has bothered to include a fully explanatory help system for the game, plus an e-mail link to send feedback. You can play your own iPod music; none is included. The Classic version drops the multiple skins and some of the options, while having only 250 puzzles versus the Unlimited version’s randomly-generated ones; it used to be $1, and is now free. We really liked the look of the Unlimited Version’s interface, and feel that the free version is a stronger introduction to the game at no charge than some companies give you for $1-2. iLounge Rating for Unlimited: B. iLounge Rating for Classic: B+.
Another of the standout versions is the professionally-developed Sudoku Vol. 1 ($6) by Japan’s Hudson Soft. In addition to six plain wallpapers and six fonts—notably including a Japanese font so that players can experience the game in its fully original form—the game has its own simple music and sound effects, pre-empting your iPod’s, and the ability to make guess marks on the board. Hint, undo, and redo features are included, as is an interactive tutorial. The game features 15 stages, five initially locked, with 50 puzzles a piece. It was co-developed with Nikoli, the “originator” of Sudoku. While a little too expensive relative to our top pick in this category, Platinum Sudoku, this is a good second choice with cool features of its own. iLounge Rating: B+.
As another extremely threadbare version of the game, Surf Shack Sudoku ($1) by Surf Shack Software offers a black and gray grid with white numbers, simple sound effects, and two features: a hint button and a large on-screen number keyboard. You can pick between three levels of difficulty and turn off the sound effects; iPod music is the only other audio you can hear. There isn’t any pencil-marking here, one of several omissions that limits the game’s appeal in our book to demo status; randomly generated puzzles are included. iLounge Rating: D.
Tile Sudoku ($5) by Magnetism Studios is a simple but clean-looking version of the game, where the numbers are on tiles rather than a traditional grid. The only frills here are your ability to drag and drop tiles into positions on the board, and an option to show you only tiles that might work on a given spot. Double-tapping on a spot on the board lets you do pencil-style possibility marking, which doesn’t really fit with the visual theme of the game, but at least it’s in there. Simple sound effects overlap your iPod mode audio. While this game strikes us as overpriced relative to its competitors, the reason that it didn’t rate higher, it’s not bad, and at least has nice graphics on its side. iLounge Rating: C.
Trivial Sudoku ($1) by Trivial Technology is another plain jane version of the game. Three difficulty levels are your primary options, along with a training mode that tells you immediately if you’ve made a mistake, and the ability to enable or disable marking of guesses in small characters. There are no visual or audio frills; you provide the iPod soundtrack yourself. There are only 75 puzzles here, a factor that detracts from what was otherwise just above demo-quality software. iLounge Rating: D+.
Finally, tSudoku Plus by eLogicpuzzles.com ($4) started out at $5, and though it has dropped in price, it hasn’t increased in attractiveness—it’s actually the least impressive app we’ve ever seen at this particular price point. The loading screen looks like an Apple II computer menu, and the game itself features a very basic visual rendition of the Sudoku grid with similarly simple fontography. tSudoku Plus’s only frills are the ability to upload your results to the elogicpuzzles.com web site, select from three difficulty levels or random (well, “all”) difficulty, and a set of dials that let you play a specific puzzle from the now 20,000 stored inside—you know, just in case you want to replay Sudoku puzzle number 6,453. The game will also solve a specific cell for you, but provides a time penalty to keep scores the same between ranked players. You provide your own iPod audio. Lacking possibility markings and possessing perhaps the worst graphics we’ve yet seen on the iPhone, this one also rates an F because of the outrageous price; if you have $4 to spend and you use it on this rather than Platinum Sudoku, you must be out of your mind. iLounge Rating: F.
See our other iPhone Gems features here.