Comparison

SmartGo One vs One By One

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

Head to head
About

SmartGo One

Learn, play, and improve at the ancient game of Go. This app offers adjustable board sizes, a strong AI opponent, and tools to study professional games and solve Go problems. It's designed for players of all skill levels, from beginners to masters.

Highlights
  • Adjustable board sizes (9x9 to 19x19)
  • Strong KataGo game engine
  • Study professional game records
  • Solve Go problems and tutorials
  • Pattern matching for move suggestions
  • Territory estimator
  • Game recording and annotation
Features
Read full description

SmartGo One is the only Go app you’ll need, whether you’re just getting started or already a seasoned player. Learn, play, study, and improve with SmartGo One. Experience the ancient game of Go on your iPhone, iPad, or Mac in a whole new way. Also known as igo (囲碁), wéiqí (围棋), or baduk (바둑), Go begins with an empty board that gradually fills as players surround territory and capture stones. Start with a 9x9 board and move up to 13x13 and 19x19 as your skills grow. SmartGo One adapts to your strength, automatically adjusting handicaps so games remain competitive and enjoyable. And when you’re ready for a serious challenge, the powerful KataGo-based engine delivers strong, rewarding play. But SmartGo One is far more than a way to play Go. Read interactive Go books while replaying the moves they describe to deepen your understanding. Explore a collection of more than 138,000 professional game records spanning both modern and historical masters. Improve your reading and decision-making skills with a growing library of Go problems and tutorials. Want to know how a master would handle a position on your board? SmartGo’s pattern matching technology compares your game with historical pro games and shows how strong players approached similar situations. No matter your level, SmartGo One helps you continue improving. Features include: • 9x9, 11x11, 13x13, and 19x19 board sizes • Powerful KataGo-based engine • Fast and responsive gameplay • Manual or automatic handicap adjustment • Record, annotate, and edit your games • Territory estimator • Hints and move analysis • Undo and replay controls • Tutorial with over 100 problems • Extensive user manual We value your privacy and only collect the minimum information necessary to make our apps work well for you. Learn more at https://smartgo.com/privacy.html. This app is licensed under Apple’s standard Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

One By One

Practice arithmetic, algebra, trigonometry, and calculus with a retro-style math game. Level up by solving problems, unlock new challenges, and compete on leaderboards. Enhance your skills with artifacts and strategic upgrades.

Highlights
  • Randomly generated math problems
  • Leveling system with unlockable content
  • Practice arithmetic, algebra, trigonometry, and calculus
  • Retro ASCII art and music style
  • Leaderboards and achievements
  • Math artifacts and upgrades
  • AI battle mode for targeted practice
Features
Read full description

One By One is a retro math study game built for middle and high school students looking to level up their mental math skills. Featuring randomly generated problems, the app lets you switch from basic arithmetic to advanced calculus. You can also target specific practice areas using the One By One Battles mode or the premium Sandbox mode. Key Features Retro Calculator Aesthetic: Enjoy a nostalgic UI designed with classic Unicode and ASCII art, complete with satisfying mechanical key clicks and atmospheric background music. Four Math Disciplines: Practice everything from basic arithmetic and high school algebra to trigonometric functions (complete with a built-in unit circle) and calculus derivatives. Leveling System: Progress all the way from Level 1 to 99, unlocking brand-new question tiers every ten levels. AI Battles & Training: Test your speed in targeted training modes or race against AI opponents to earn in-game rewards. Artifacts & Upgrades: Solve rare "Golden Problems" to collect 25 unique math artifacts featuring 9 distinct upgrades to shape your strategy. Leaderboards & Achievements: Compete across 5 specialized leaderboards, including a balance-based leaderboard, and uncover hidden achievements. Download One By One and start solving math faster than your teacher! Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

SmartGo One4 screens
One By One4 screens

Verdict

The call

The clearest difference is ads: SmartGo One at none against One By One's shown. SmartGo One also leads on ratings volume (2K vs 77). One By One's advantage is review sentiment (91% vs 77%) and iOS requirement (15.0 vs 26.0). On price, rating, update cadence 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. SmartGo One sells 47 in-app purchases, starting at $4.99 per month and One By One sells 3 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for SmartGo One against 4.8 for One By One. That said, the two scores are not equally well evidenced: SmartGo One has 2K ratings behind it against 77, so its average is the more settled of the two. Written reviews are what separate them: 77% of SmartGo One's written reviews are positive against 91% of One By One's.

UpkeepUpdate frequency

SmartGo One ships an update every 10 days, One By One every 2 weeks. The most recent releases landed on October 19, 2026 and October 13, 2026 respectively.

Scorecard4 real differences · 6 level
SmartGo One versus One By One: the parameters behind the verdict, then further details
ParameterSmartGo OneOne By One
PriceFreeFree
Rating4.8 (2K ratings)4.8 (77 ratings)
Positive reviews76.6% of reviews90.9% of reviews — better
Number of ratings2K — better77
Update frequencyEvery 10 days — betterEvery 2 weeks
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS26.015.0 — better
Further details — not scored
Size154 MB64 MB
Age rating4+4+
DeveloperSmart Go, Inc.Brice Brown

Customer experience

SmartGo One

All ratings1,955 ratings
Positive95.7%
Neutral2.3%
Negative2.1%
Written reviews167 reviews
Positive76.6%
Neutral8.4%
Negative15.0%

One By One

All ratings77 ratings
Positive94.8%
Neutral1.3%
Negative3.9%
Written reviews22 reviews
Positive90.9%
Neutral4.5%
Negative4.5%

Bugs and requests

SmartGo One

Reported bugs

3 issues
  • Illegal move detection issues on certain board positions
  • Problems with missing variations or incorrect answers
  • Inconsistent behavior when passing moves

Requested features

5 requests
  • Add read-only mode
  • Improve move suggestion explanations
  • Introduce difficulty settings for AI
  • Integrate online play functionality
  • Provide more randomness in AI moves

One By One

Not enough reviews yet to summarise bugs or requests.

In-app purchases

47 purchases

SmartGo One

Subscriptions2
  • SmartGo One Pro – Monthly$4.991 Month
  • Pro Games and Features14 Days trial$29.991 Year
One-time45
  • Just Enough Japanese 1Free
  • Key Concepts in Life and Death$2.99
  • Go Problems Master Collection$3.99
Show 42 more
  • Go Problems Add-on 2: Medium$3.99
  • Go Problems Add-on 1: Easy$3.99
  • Go Problems Add-on 3: Hard$3.99
  • Counting Liberties$4.99
  • The Monkey Jump$4.99
  • Double Digit Kyu Games$5.99
  • Go: A Complete Introduction$5.99
  • How Not to Play Go$5.99
  • Encyclopedia of Go Principles$5.99
  • Want to Play Go? Level 1$5.99
  • Black to Play 30-25 Kyu$5.99
  • The Workshop Lectures 1$5.99
  • Rethinking Opening Strategy$6.99
  • Learn to Play Go 1$7.99
  • Learn to Play Go 2$7.99
  • Learn to Play Go 3$7.99
  • Correct Joseki$7.99
  • “The Theory of Go”$7.99
  • Learn to Play Go 4$7.99
  • Buddhist Philosophy Game of Go$8.99
  • Graded Go Problems 1$9.99
  • Graded Go Problems 2$9.99
  • Want to Play Go? Level 2$9.99
  • Basic Techniques of Go$9.99
  • Graded Go Problems 3$9.99
  • Get Strong at Life and Death$9.99
  • Mastering Mini Go by Mark Tomlinson$11.99
  • Fuseki Revolution$11.99
  • Fundamental Principles of Go$11.99
  • The Basics of Life and Death$11.99
  • Joseki Revolution$11.99
  • Life and Death$11.99
  • A Survey of the Basic Tesujis$11.99
  • Tesuji$11.99
  • Tesuji for Beginners$14.99
  • AlphaGo to Zero, vol. 4$14.99
  • Trouble Master, volume 2$14.99
  • Trouble Master, volume 1$14.99
  • AlphaGo to Zero, Vol. 2$14.99
  • Invincible$24.99
  • Essential Go Proverbs$24.99
  • Pro – Lifetime Unlock$99.00
3 purchases

One By One

Subscriptions2
  • Monthly Support$1.991 Month
  • Yearly Support$12.991 Year
One-time1
  • Lifetime Supporter pass$19.99

Questions

Is SmartGo One free?
SmartGo One is free to download, with in-app purchases available.
Is One By One free?
One By One is free to download, with in-app purchases available.
Which has better reviews, SmartGo One or One By One?
SmartGo One and One By One are both rated 4.8 out of 5 on the App Store, from 2K and 77 ratings respectively.
Do SmartGo One or One By One have ads?
One By One shows ads; SmartGo One does not.
Which is updated more often, SmartGo One or One By One?
SmartGo One ships an update every 10 days, and One By One every 2 weeks. Most recently, SmartGo One was updated on October 19, 2026 and One By One on October 13, 2026.

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