Sudoku Royale vs Tripledot Sudoku: Undo, Ads and Levels

Tripledot Sudoku lets you set the rules: unlimited undo, an eraser, auto-check you can switch off and a three-mistake limit you can switch on. It shows ads, and its listing shows no purchase that removes them. Sudoku Royale fixes the rules instead (every number is checked, no undo) and spends its effort on what comes next: two levels above Expert, a daily puzzle with a leaderboard, and lessons on the techniques the hard puzzles need. It has no ads and nothing to buy. Which one suits you depends mostly on how you solve: by trying numbers and taking them back, or by finding the one move the grid allows.

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.

Feature by feature

What happens when you place a wrong number

This is where the two apps feel most different in the hand.

In Tripledot, you decide. With auto-check on, a wrong digit is flagged and you clear it with the eraser or undo. With auto-check off, the mistake sits there until the grid stops making sense, and finding it is part of the puzzle, as it is on paper. Turn on the mistake limit and three errors end the game, which makes even an easy grid tense. Unlimited undo means you can also explore: put in a number, follow it a few moves, and roll back if it breaks.

In Sudoku Royale, a wrong number is rejected the moment you place it, every time, and there is no undo. You cannot build on a mistake, so you never spend ten minutes hunting one, but you also cannot test a guess and take it back. Practice has no mistake limit at all; the Daily Challenge gives you three lives and adds 30 seconds per mistake, and after the third you can finish but the run is unranked. If you play by trial and error, Tripledot fits you better. If you want to solve by logic alone, our guide on whether sudoku can be solved without guessing looks at how far logic alone can take you.

After Expert

Tripledot's listing describes four levels, Easy to Expert, and "thousands" of puzzles. When Expert stops being hard, that is the ceiling. Sudoku Royale adds Master and Extreme, unlocked by solving at the level below, from a library of about 500,000 puzzles. Those top levels call for techniques beyond singles and pairs, like X-Wing and Swordfish. The Journey walks through them a chapter at a time, and the Dojo lets you drill one pattern until it is automatic. Royale's hint fits the same idea: it names the technique and the cell and leaves the number to you.

Ads, and the price of avoiding them

Tripledot's puzzles are free, and its listing calls them "totally free". Its App Store age rating notes advertising, and its listing shows no purchase that removes them. It has been on the App Store since 2018 with 104,197 US ratings, so many players clearly find the trade acceptable. Sudoku Royale shows no ads and has no in-app purchases or subscription; the avatar outfits in its shop cost shurikens you earn by solving. If ads are the only reason you are reading this, the Tripledot Sudoku alternatives page compares several ad-free and pay-once options, not just ours.

Where Tripledot Sudoku is the better pick

• You solve by trying and undoing. Unlimited undo and an eraser; Royale has neither.
• You want to choose the rules. Auto-check off, a mistake limit on, or any mix.
• Notes that look after themselves. Its listing says pencil notes update automatically as you play. Royale clears notes when you place a number, but you write every candidate yourself.
• You like a choice of looks. Six skins against Royale's light and dark.

Where Sudoku Royale is the better pick

• No ads, at no cost. Nothing to buy and nothing shown between puzzles.
• A higher ceiling. Master and Extreme, with lessons for the techniques they need.
• A daily puzzle you share. One puzzle a day for everyone, a streak, a leaderboard and an archive of past days.
• Hints that teach. See how sudoku hints should work.

Which should you choose?

Stay with Tripledot if undo and adjustable rules are how you enjoy sudoku and the ads do not get in your way. If you would rather play a clean grid with no ads, and you are ready for puzzles beyond Expert, download Sudoku Royale. Compare another plain classic in Sudoku Royale vs Staple Games, or see every matchup on the sudoku app comparisons page.