Comparison

Zero? vs Knight Tour Trainer

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

Head to head
About

Zero?

A fast-paced number game where players must quickly determine if sums of numbers are multiples of ten. Offers various modes for solo play or head-to-head challenges with friends.

Highlights
  • Sum calculation challenges
  • Timed gameplay
  • Relaxed mode without time pressure
  • Two-player head-to-head mode
  • Multiplayer on a single device
Features
Read full description

Can you tell if the sum of 3 numbers are a multiple of ten? 4 numbers? More? It sounds easy, but hurry... time is running out! Challenge your friends, and play face-to-face on a single iPad or iPhone! Fun for all ages, choose your favourite mode: • Zoom & Zen, for a fast or easy-paced challenge • Relax, for stress-free fun without the time pressure • Two-player, the unique way to play with your friends in head-to-head action! Reviews for Sum Fun: “ It’s a solid math game, one that brings in interesting gameplay ideas and which has a stellar execution ” – AppGames.net: 9 / 10 “ By the time your kids have played with this app a few times, they’ll be adding up the numbers faster than you can say, ‘What’s six plus eight?’ ” – Fun2Tap: 5 / 5

About

Knight Tour Trainer

Features
Read full description

Knight Tour is a classic chess puzzle: move the knight so it visits every square exactly once. Train your logic and concentration while solving increasingly challenging boards. Features: • Multiple board sizes (from beginner to expert) • Clean and intuitive gameplay • Light & dark themes • Smart hints to guide your moves • Achievements to track your progress • Game Center leaderboards — compete for first place on every board • Complete full tours, earn achievements, and become the Champion Perfect for fans of chess, puzzles, and brain training games.

Screenshots

Zero?4 screens
Knight Tour Trainer4 screens

Verdict

The call

The clearest difference is iOS requirement: Zero? at 8.0 against Knight Tour Trainer's 14.0. On price, update cadence, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 24, 2026 and October 7, 2026 respectively.

Scorecard1 real difference · 9 level
Zero? versus Knight Tour Trainer: the parameters behind the verdict, then further details
ParameterZero?Knight Tour Trainer
PriceFreeFree
Rating4.0 (3 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings3 — better—
Update frequencyEvery 3 monthsEvery 3 months
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS8.0 — better14.0
Further details — not scored
Size27 MB76 MB
Age rating4+4+
DeveloperGreg SharpeVitalii Medvediev

In-app purchases

None

Zero?

No in-app purchases

None

Knight Tour Trainer

No in-app purchases

Questions

Is Zero? free?
Zero? is free to download, with no in-app purchases.
Is Knight Tour Trainer free?
Knight Tour Trainer is free to download, with no in-app purchases.
Do Zero? or Knight Tour Trainer have ads?
Neither Zero? nor Knight Tour Trainer shows ads.
Which is updated more often, Zero? or Knight Tour Trainer?
Zero? ships an update every 3 months, and Knight Tour Trainer every 3 months. Most recently, Zero? was updated on October 24, 2026 and Knight Tour Trainer on October 7, 2026.

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