# TwentyOne: Blackjack Trainer — Learn perfect basic strategy > Blackjack basic strategy trainer with customizable rules and card counting drills. (iPhone/iPad app by Justin Taddeo.) - Source: https://appshunter.io/ios/app/twentyone-blackjack-trainer/id6781118717 (this page in markdown: same URL + `.md`) - Developer: [Justin Taddeo](https://appshunter.io/developer/1885201658) - Category: Games, Casino - Price: Free with in-app purchases - Rating: 5.00/5 from 1 App Store ratings · 1 written reviews indexed - Age rating: 17+ - Requires: iOS 17.0 · 2 MB - Languages: English - Released: 2026-06-26 - Data updated: 2026-07-24 - Monetization: freemium - User reviews in markdown: https://appshunter.io/ios/app/twentyone-blackjack-trainer/id6781118717/reviews.md ## What is TwentyOne? TwentyOne is a clean, focused blackjack basic-strategy trainer. Learn the mathematically correct play for every hand, then drill it until it's second nature — in a calm, minimalist interface with no ads and no clutter. WHY TWENTYONE Basic strategy is the proven, optimal way to play every blackjack hand. TwentyOne doesn't just show you a chart — it computes the correct play for your exact table rules and helps you commit it to memory through fast, focused practice. THE STRATEGY CHART • The complete chart for hard totals, soft hands, and pairs • Color-coded for Hit, Stand, Double, Split, and Surrender • Tap any cell to see the expected value behind every option • Recomputes instantly when you change the rules PRACTICE THAT STICKS • Deal a hand, choose your action, and see the correct play right away • Modes: Random, Hard Totals, Soft Hands, Pairs, and Most Missed • "Most Missed" automatically resurfaces the hands you get wrong • Track your accuracy, streak, and performance by hand type PLAYS BY YOUR RULES Real tables differ, and so does correct strategy. Configure: • Number of decks (2, 4, 6, or 8) • Dealer hits or stands on soft 17 (H17 / S17) • Double after split, double rules, and late surrender • Resplit aces, hit split aces, and more The chart and every practice answer adjust automatically. TWENTYONE PRO Take your training further with a single one-time purchase — no subscriptions, no ads: • Expected value on every hand — see the full EV breakdown behind your decision after each practice hand, not just in the chart • Card Counting Trainer — master the Hi-Lo system with four focused drills: – Card Values: flash through the +1 / 0 / −1 tags until they're instant – Running Count: keep an accurate count as cards are dealt – Deck Countdown: race through a full deck down to zero – True Count: convert running count to true count on the fly Everything else in TwentyOne is free. MADE TO LOOK GOOD • Minimalist design with crisp, simple cards • Full light and dark mode • Three app icons to choose from • No ads, no accounts, no tracking — works offline for all training TwentyOne is for study and entertainment. It teaches optimal decision-making and involves no real-money play and no wagering. ## Key features - Basic strategy chart for all hands - Customizable table rules - Practice modes for hands and pairs - Performance tracking - Expected value calculations - Card counting trainer (Hi-Lo system) ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | TwentyOne Pro | $4.99 | one-time | ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/twentyone-blackjack-trainer/id6781118717/reviews.md ### 5/5 — Best on the market *2026-07-13* Easy training tool for beginners, or even good players. I use this on the plane to Vegas to get sharp. Great app. ## Frequently asked questions about TwentyOne ### Does TwentyOne have ads? No, TwentyOne is ad-free. The app is designed with a minimalist interface and no advertisements for an uninterrupted learning experience. ### How much does TwentyOne cost? The core blackjack basic strategy trainer is free. Advanced features, including the expected value breakdown and card counting trainer, are available with a one-time purchase called TwentyOne Pro. ### Can I play TwentyOne offline? Yes, all training features in TwentyOne work offline. The app does not require an internet connection for practice or strategy learning. ### What blackjack rules can I customize in TwentyOne? You can configure the number of decks (2, 4, 6, or 8), whether the dealer hits or stands on soft 17, double after split rules, late surrender, and more. The strategy chart and practice answers adjust automatically to your chosen rules. ### What is the age rating for TwentyOne? TwentyOne has an age rating of 17+. This is likely due to its association with casino games and gambling concepts. ### How often is TwentyOne updated? The latest version, 1.1.21, was released on June 26, 2026, indicating recent development activity. Updates typically focus on refining features and ensuring compatibility. ### What are the card counting drills in TwentyOne Pro? TwentyOne Pro includes four focused drills for the Hi-Lo card counting system: Card Values, Running Count, Deck Countdown, and True Count. These help users master the system for practical application. ### What is the user sentiment for TwentyOne? Based on the available data, user sentiment appears to be highly positive, with a rating of 5.0 stars from 1 rating. This suggests users find the app effective and well-designed. ## Version history (last 2 releases) ### 1.2.1 — 2026-07-14 TwentyOne comes to iPad! The full trainer, redesigned for the big screen — a larger strategy chart that fits edge to edge, full-size practice cards, and tap-anywhere details in both portrait and landscape. Plus: strategy explanations now appear in the chart too — tap any hand to see why the play is right. ### 1.1.21 — 2026-06-26 No release notes. ## More apps by Justin Taddeo - [MatchPlay - Golf Tracker](https://appshunter.io/ios/app/matchplay-golf-tracker/id6760590739) All apps by Justin Taddeo: https://appshunter.io/developer/1885201658 --- *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 2026-07-24.*