
Simon's Bacteria
COGNITIVE LABS
0 ratings
Free
In-App Purchases
About
Simon's Bacteria is a turn-based strategy game built around one deceptively simple mechanic: rotate a stone, and watch the board change.
HOW IT WORKS
Each stone on the board points in one of four directions. On your turn, rotate one of your stones 90° clockwise — it moves into the cell it now points to, and can trigger a chain reaction of captures across the board. Read the board carefully: a single rotation can flip the momentum of the entire game.
PLAY TOGETHER
Challenge your friends through Game Center and play together across iPhone, iPad, and Mac. Choose your favorite game mode, compete for victories, unlock achievements, and jump straight into a rematch. Your first 3 multiplayer games are free — after that, a one-time purchase unlocks unlimited multiplayer for good.
• Multiplayer across iPhone, iPad, and Mac
• Three unique game modes
• Game Center achievements and statistics
• Quick rematches with friends
PLAY YOUR WAY
• Chaos Mode — a fully randomized board for a classic, unpredictable game every time.
• Symmetry Mode — mirrored starting positions for a perfectly fair fight.
• Balanced Mode — randomized but evenly distributed starting directions.
THREE LEVELS OF AI (VINTAGE 1998)
No neural networks, no cloud, no buzzwords — just an honest, old-school game AI in the spirit of 1998, built on classic move-search logic rather than anything fashionable. It adapts to the difficulty you choose — from a forgiving opponent that favors easy captures, to a sharp one that looks several moves ahead and plans around your counter-attacks.
DESIGNED TO GET OUT OF YOUR WAY
• Clean, focused board — no clutter, no timers pressuring your every move.
• Three visual stone styles to match your taste.
• Game Center leaderboards and achievements to track your wins.
• Your games and stats are saved locally — pick up right where you left off.
• No ads. No account required for single-player. No data collection beyond what Game Center itself handles.
FREE TO PLAY, OPEN SOURCE
Single-player is completely free, forever, with everything unlocked — it's an open-source passion project. Multiplayer includes 3 free games to try it out, then a small one-time purchase for unlimited play. If you'd like to say thanks separately, optional tips are available in the Tips menu; they simply help cover the cost of the Apple Developer license required to bring an open-source project like this one to the App Store.
Whether you have two minutes or twenty, Simon's Bacteria rewards careful thinking over fast reflexes.
COMING SOON
We're actively working on additional board generation modes and new AI difficulty tiers.
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What's New in Simon's Bacteria
2.0.2
August 22, 2026
Multiplayer Unlock is now available directly from the in-game menu at any time — there is no need to use all three free games first. This update also improves the purchase screen and makes unlock status clearer across iPhone, iPad, and Mac.
More3
In-App Purchases
$0.99
Small Tip
App is 100% free — this is just a thank-you

