Comparison

Chess King vs BioDecoder

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

Head to head
About

Chess King

Master the game of chess with this comprehensive learning app. It offers interactive lessons, puzzles, and analysis for all skill levels, from beginner to advanced. Improve your tactics and strategy with a personal chess trainer, available online and offline.

Highlights
  • 100+ learning courses
  • Interactive theoretical lessons
  • High-quality, double-checked puzzles
  • Personal chess trainer
  • Computer analysis
  • Offline support
  • Chess tasks for kids
Features
Read full description

Don't just play chess. Train like a master. Chess King teaches the game the way strong players are actually built — with a rigorous, structured curriculum, not a random feed of puzzles. 147 complete courses take you from your first move to advanced play, step by step. WHY CHESS KING IS DIFFERENT Most chess apps let you play. Chess King trains you. Every course is a real lesson built on classical training methods refined over 30 years — the same approach behind CT-ART, the tactics trainer used by serious players worldwide. You don't just solve a position and move on. Chess King gives you hints when you are stuck, explains the idea behind the right move, and shows you the striking refutation of the mistakes you might make. That is how understanding is built — not memorized. WHAT YOU GET - 147 structured courses covering tactics, strategy, openings, the middlegame, and endgames, organized by level from beginner to master. - Chess King University: 7 guided learning paths and 44 courses that give you a clear, ordered route to real improvement — no guessing what to study next. - Interactive theory: read the lesson, then play the moves on the board yourself. Learning by doing, not just reading. - Thousands of carefully selected exercises with graphic hints and full explanations. - Play against the computer to put what you have trained into practice. - A progress report for every lesson, so you always see how far you have come. TRAIN ON EVERY DEVICE Your subscription, purchases, progress, and rating sync automatically across web, iPhone, iPad, and Android. Train on your phone on the commute, continue on the web at home — your progress follows you. TRY IT FREE Preview courses before you commit. When you are ready, choose a monthly or yearly plan, or buy individual courses to keep forever. Chess King — train like a master. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

BioDecoder

Features
Read full description

Enter the world of BioDecoder, a thrilling puzzle experience where logic, memory, and deduction are your greatest weapons. Humanity’s future is on the line – a mysterious code holds the key to survival, and only you can break it. Your mission is simple to explain but challenging to master: uncover the correct sequence before time runs out. Each guess brings you closer to the solution, but also tests your ability to think ahead, eliminate possibilities, and adapt to new challenges. With multiple difficulty levels – from relaxed brain-teasing to extreme code-breaking – BioDecoder is designed for both casual players and true puzzle veterans. Every level offers a fresh challenge, ensuring the game stays engaging no matter how many times you play. Features: • Engaging code-breaking gameplay inspired by timeless classics, with a modern twist. • Four difficulty levels: Beginner, Medium, Hard, and Extreme. • Stylish, clean interface for an intuitive and immersive experience. • Built-in haptic feedback for a tactile feel to every action. • Play at your own pace or race against the clock in timed modes. Whether you have a few minutes to spare or want to sink into an intense puzzle session, BioDecoder offers the perfect mental workout. Can you crack the code and save humanity?

Screenshots

Chess King4 screens
BioDecoder3 screens

Verdict

The call

The clearest difference is ads: BioDecoder at none against Chess King's shown. Chess King's advantage is device support (4 vs 1) and iOS requirement (13.0 vs 18.5). On price, 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. Chess King sells 17 in-app purchases, starting at $5.99 per month and BioDecoder sells 3 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Chess King ships an update every 3 weeks, BioDecoder fortnightly. The most recent releases landed on October 19, 2026 and October 14, 2026 respectively.

Scorecard3 real differences · 7 level
Chess King versus BioDecoder: the parameters behind the verdict, then further details
ParameterChess KingBioDecoder
PriceFreeFree
Rating4.8 (2.5K ratings) — better—
Positive reviews78.4% of reviews—
Number of ratings2.5K — better—
Update frequencyEvery 3 weeksFortnightly — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod, Mac — betteriPhone
Requires iOS13.0 — better18.5
Further details — not scored
Size109 MB2 MB
Age rating4+12+
DeveloperChess KingRichard Magney

Bugs and requests

Chess King

Reported bugs

5 issues
  • Crashes on M1 Macs
  • Doesnot work with iOS 13 dark mode
  • Doesnot show board and pieces in exercises
  • Cannot restore purchases
  • Doesnot sync progress across devices

Requested features

7 requests
  • Add dark mode option
  • Improve user interface and design
  • Add more opening courses
  • Provide better explanations for moves
  • Allow resetting progress
Show 2 more
  • Improve syncing across devices
  • Add online chess mode

BioDecoder

Not enough reviews yet to summarise bugs or requests.

In-app purchases

17 purchases

Chess King

Subscriptions6
  • CT-ART: The Best Tactics7 Days trial$5.991 Month
  • Chess King University7 Days trial$11.991 Month
  • Chess King Courses3 Days trial$11.991 Month
Show 3 more
  • Chess King Maximum Pack1 Month trial$17.991 Month
  • Chess King Courses3 Days trial$89.991 Year
  • Chess King Maximum Pack1 Year trial$119.991 Year
One-time11
  • Mate in 1 move (Chess Puzzles)$3.99
  • Chess Endings for Beginners$7.99
  • Chess: From Beginner to Club$12.99
Show 8 more
  • Chess Combinations Vol. 1$12.99
  • Chess Tactics for Beginners$12.99
  • Chess Opening Blunders$12.99
  • Chess Opening Lab (1400-2000)$12.99
  • Chess Strategy for Beginners$12.99
  • Elementary Chess Tactics 1$12.99
  • CT-ART 4.0 (Chess Tactics)$17.99
  • Total Chess Endgames 1600-2400$17.99
3 purchases

BioDecoder

One-time3
  • Small Tip$0.99
  • Medium Tip$3.99
  • Large Tip$8.99

Questions

Is Chess King free?
Chess King is free to download, with in-app purchases available.
Is BioDecoder free?
BioDecoder is free to download, with in-app purchases available.
Do Chess King or BioDecoder have ads?
Chess King shows ads; BioDecoder does not.
Which is updated more often, Chess King or BioDecoder?
Chess King ships an update every 3 weeks, and BioDecoder fortnightly. Most recently, Chess King was updated on October 19, 2026 and BioDecoder on October 14, 2026.

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