# Thirty-One

> Thirty-One (iPhone/iPad app by Koichi Iwasaki.)

- Source: https://appshunter.io/ios/app/thirty-one/id6756990237 (this page in markdown: same URL + `.md`)
- Developer: [Koichi Iwasaki](https://appshunter.io/developer/1308795626)
- Category: Games, Card
- Price: Free
- Age rating: 4+
- Requires: iOS 13.0 · 101 MB
- Languages: American English
- Released: 2025-12-30
- Data updated: 2026-05-19
- User reviews in markdown: https://appshunter.io/ios/app/thirty-one/id6756990237/reviews.md

## What is Thirty?

"Simple yet deep! The classic card game ”31 (Thirty-One)” is now available as an app! Experience thrilling tactics as you try to get your hand total as close to 31 as possible. The rules are simple, but winning requires real strategy. From beginners to pros, this is the definitive card game for everyone.

◆ Face off against unique rivals! Challenge nine distinct characters, each with their own playstyle:

Newbie: A beginner whose unpredictable moves might surprise you.
Aggressor: A bold player who loves to ”Knock” early.
Tactician: A strategist who calculates maximum efficiency.
Stoic: A steady player who prioritizes not losing above all else.
CPU Master: The ultimate AI that calculates every probability.

◆ Customize the rules your way! Fine-tune the game settings to match your favorite playstyle:
Should Aces (A) count as 11 points?
Should Three-of-a-Kind count as 30.5 points?
Will you allow ”Blitz” or ”Sweep”?
Use your best strategy to defeat the ultimate CPU Master!"


## Version history (last 2 releases)

### 1.0.1 — 2026-02-20

Optimized CPU AI and decision-making logic.
Fixed a display bug during CPU actions.
Improved game flow and pacing.

### 1.0.0 — 2025-12-30

No release notes.

## More apps by Koichi Iwasaki

- [Samurai Drama](https://appshunter.io/ios/app/samurai-drama/id1308795627)
- [SevenNarabe](https://appshunter.io/ios/app/sevennarabe/id1439039394)
- [Old Maid(Babanuki)](https://appshunter.io/ios/app/old-maidbabanuki/id1444817189)
- [CONCENTRATION(神経衰弱ゲーム)](https://appshunter.io/ios/app/concentration/id1447839201)
- [Speed(Card game)](https://appshunter.io/ios/app/speedcard-game/id1451181232)
- [Butanoshippo(Card game)](https://appshunter.io/ios/app/butanoshippocard-game/id1452783527)

All apps by Koichi Iwasaki: https://appshunter.io/developer/1308795626

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-05-19.*