Best Sudoku App for iPhone: iOS Versions, Size, Landscape

On a recent iPhone, Sudoku Royale is our pick if you want a free app with no ads and nothing to buy; it needs iOS 17 or later and plays in portrait only. If you want to turn the phone sideways, Brainium Sudoku and nerByte Sudoku both list landscape play. If your iPhone is too old for iOS 17 or later, Sudoku by Mind The Frog and Stress Free Sudoku still install on iOS 12.4 or later and iOS 12 or later. The rest of this page is about what changes on the phone itself: which iOS each app needs, how much space it takes, whether it uses Game Center, and whether it tracks you across other apps.

The App Store facts

From each app's US App Store listing, checked October 26, 2026. Prices and paid items change, so check the listing before you buy.

The iPhone details, app by app

Numbers below come from each app's US App Store listing. The landscape column quotes the listing where it says something; "Not stated" means the listing is silent, not that the app cannot do it.

Older iPhones: check the iOS line first

The first thing that rules an app out is the iOS version it needs. Sudoku Royale needs iOS 17 or later. iOS 17 runs on the iPhone XS, XR and later models, so an iPhone 8 or X handed down to a parent cannot install it. Mind The Frog's app asks for iOS 12.4 or later and Stress Free Sudoku for iOS 12 or later, so both still run on much older phones. Look up your version in the Settings app, under General, About.

Storage: a small app or a big one

Sudoku apps differ in size by a wide margin. Mind The Frog's listing makes a point of it ("doesn't eat up a lot of storage"), and at 6 MB it is the smallest here. Sudoku Royale is 43 MB. Brainium Sudoku, with its backdrops and animations, is 331 MB. On a 64 GB phone full of photos that gap matters more than any feature list.

Holding it: portrait, landscape and one hand

Most people play sudoku on a phone upright, in one hand. Sudoku Royale only does portrait on iPhone, with the board in the middle and the number keys and Notes switch at the bottom, and it lets you place digits without leaving the grid: tap a cell and a number picker opens over the board, or press and slide to the digit in one move. Our guide to playing sudoku on iPhone covers grip and input in detail, and slide to select explains the gesture.

If you prefer the phone on its side, propped on a table or a train tray, Brainium Sudoku lists portrait and landscape play with a right or left-handed option in landscape. nerByte Sudoku lists landscape and portrait plus Display Zoom support for larger controls. Mind The Frog's listing promises "big buttons" to avoid mistaps.

Game Center, sync and tracking

Game Center gives you leaderboards and achievements tied to your Apple account. Sudoku Royale uses it for leaderboards, and Sign in with Apple or Game Center is optional: you can play as a guest. Your progress syncs through Sudoku Royale's own server account, not iCloud, so signing in is what carries it to an iPad. Sudoku.com's listing does not list Game Center.

Apple's privacy label is the other thing worth reading before you install. Sudoku Royale's listing has no "Data Used to Track You" section. The table shows which others do. For more on this, see the most private sudoku apps.

The picks

• Free, no ads, recent iPhone: Sudoku Royale. Six levels of unlimited Practice, a Daily Challenge, hints that name the technique, and nothing to buy. It is new, with 11 US ratings.
• Landscape, or left-handed sideways play: Brainium Sudoku. It shows ads unless you pay; its price line is Free, ads (remove for $11.99).
• Landscape plus a one-time ad removal: nerByte Sudoku, which also lists unrestricted offline play. Its Sudoku No Ads item costs $7.99.
• Old iPhone or little storage: Sudoku by Mind The Frog, with undo and redo and automatic notes.
• The biggest community: Sudoku.com, with 1.87 million ratings; ads go with Sudoku.com No Ads at $14.99.

Where Sudoku Royale is not the right iPhone app

• You want undo or automatic pencil marks. It has neither; every number is checked as you place it instead.
• You want to hide the timer. It always shows in Practice. Stress Free Sudoku lists no timers at all.
• You want a home screen widget or an Apple Watch app. Sudoku Royale has neither.
• You want to switch off haptics inside the app. There is no in-app switch.

If none of those matter to you, get Sudoku Royale for iPhone. For the iPad side, see the best sudoku apps for iPad; for a ranking that is not about the device, the best sudoku apps; and for every matchup, the comparisons page.