# 21 Sharp — Master Blackjack Strategy

> Blackjack strategy trainer for basic strategy and card counting. (iPhone/iPad app by busyslacker llc.)

- Source: https://appshunter.io/ios/app/21-sharp/id6757319502 (this page in markdown: same URL + `.md`)
- Developer: [busyslacker llc](https://appshunter.io/developer/1576079901)
- Category: Education, Entertainment
- Price: Free with in-app purchases
- Rating: 5.00/5 from 1 App Store ratings
- Age rating: 12+
- Requires: iOS 17.0 · 1 MB
- Languages: American English
- Released: 2026-02-12
- Data updated: 2026-07-01
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/21-sharp/id6757319502/reviews.md

## What is 21 Sharp?

Turn the odds in your favor.

21 Sharp is a professional-grade blackjack trainer that teaches you basic strategy and card counting—the same techniques used by advantage players to beat the house.

BASIC STRATEGY TRAINING
Learn the mathematically optimal play for every possible hand. Our quiz system drills you on 270+ hand combinations until perfect strategy becomes second nature. Reduce the house edge to just 0.5%.

CARD COUNTING DRILLS
Master the Hi-Lo counting system with speed-building exercises. Track running counts, calculate true counts, and learn when to increase your bets. Practice until you can count down a full shoe with accuracy.

PRACTICE TABLE
Play realistic blackjack hands with real-time strategy hints. See the running count, get recommendations for every decision, and learn from your mistakes without risking real money.

REFERENCE GUIDES
Access complete basic strategy charts and a comprehensive Hi-Lo counting guide anytime. Perfect for quick review before hitting the casino.

TRACK YOUR PROGRESS
Unlock 25+ achievements as you improve. Monitor your accuracy, streaks, and stats across all training modes. Watch yourself transform from beginner to sharp.

Whether you're preparing for Vegas, want to impress at home games, or just love the math behind the game, 21 Sharp gives you the edge.

Play Sharp. Win Sharp.

## Key features

- Basic strategy training
- Card counting drills (Hi-Lo)
- Realistic practice table
- Reference guides
- Progress tracking and achievements

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| 21 Sharp Premium | $2.99 | one-time |



## Frequently asked questions about 21 Sharp

### What is 21 Sharp?

21 Sharp is a professional-grade blackjack trainer designed to teach users basic strategy and card counting techniques. It aims to help players reduce the house edge and improve their game.

### Does 21 Sharp have ads?

No, 21 Sharp does not contain advertisements. The app is free to download and use, with optional in-app purchases available for enhanced features or content.

### What learning methods does 21 Sharp use?

21 Sharp employs a quiz system for basic strategy, drilling over 270 hand combinations. It also offers speed-building exercises for card counting and realistic practice hands with real-time hints.

### Can I track my progress in 21 Sharp?

Yes, 21 Sharp allows you to track your progress by unlocking over 25 achievements. You can monitor your accuracy, streaks, and statistics across all training modes.

### What card counting system does 21 Sharp teach?

21 Sharp focuses on teaching the Hi-Lo counting system. It includes exercises to master tracking running counts, calculating true counts, and learning when to adjust bets.

### What devices is 21 Sharp available on?

21 Sharp is available on iPhone and iPad devices. It is designed for mobile use, allowing practice anytime, anywhere.

### How often is 21 Sharp updated?

The latest version of 21 Sharp is 1.0, and it was last updated on February 12, 2026. As a newer application, future updates will likely focus on adding new features and refining existing ones.

### What is the age rating for 21 Sharp?

21 Sharp has an age rating of 12+. This indicates it is suitable for users aged 12 and older, considering its educational content related to card games.

## Version history (last 1 release)

### 1.0 — 2026-02-12

No release notes.

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## More apps by busyslacker llc

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All apps by busyslacker llc: https://appshunter.io/developer/1576079901

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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 2026-07-01.*