# Basis21: Blackjack Trainer — Perfect Basic Strategy > Perfect Basic Strategy (iPhone/iPad app by VINCENT WAH KIT WONG.) - Source: https://appshunter.io/ios/app/basis21-blackjack-trainer/id6787679130 (this page in markdown: same URL + `.md`) - Developer: [VINCENT WAH KIT WONG](https://appshunter.io/developer/6782601296) - Category: Education - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 15.0 · 14 MB - Languages: American English - Released: 2026-07-14 - Data updated: 2026-08-03 - User reviews in markdown: https://appshunter.io/ios/app/basis21-blackjack-trainer/id6787679130/reviews.md ## What is Basis21? Basis21 teaches you the mathematically correct play for every blackjack hand — not general tips, but the exact, EV-optimal decision for the specific rules at your table. HOW IT WORKS • Pick your casino's exact rule set (deck count, dealer soft-17 behavior, doubling restrictions, surrender availability, and more) — Basis21 ships with presets for major casinos and lets you fine-tune any rule. • Drill: get dealt random hands and choose your play. Basis21 grades every decision instantly, shows the correct action and the EV difference if you got it wrong — and with Continue after Hit, you can draw a real card and play the hand one move further instead of stopping at the first decision. • Strategy Chart: browse the full basic-strategy chart for your rule profile, with an EV breakdown behind every cell so you understand why it's correct — not just what to memorize. • Compare: heading to a different casino? Put your usual rules side by side with the table you're about to play — see exactly how many hands change, and by how much, before you sit down. • Track your accuracy over time, see exactly which situations you're weakest on, and drill them directly — with focus modes for your weakest spots, mistakes you've made before, and the genuine close-call hands where the correct play is a coin flip. WHY BASIS21 Off-the-shelf strategy charts assume one generic rule set. Real tables vary — deck count, dealer soft-17 behavior, doubling restrictions, and surrender rules all shift the correct play. Basis21 computes strategy from first principles for your exact rules, so what you drill is what you should actually do at the table. Basis21 is a training tool for education and entertainment. It does not involve real-money wagering, betting, or gambling of any kind, and correct basic strategy narrows the house edge — it does not guarantee winning. ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Premium Unlock | $19.99 | one-time | ## Version history (last 5 releases) ### 1.2.3 — 2026-07-31 Fixed a display issue affecting some Android devices with a non-default system font size. ### 1.2.2 — 2026-07-30 Fixed a display issue on some Android devices where onboarding content could overflow the screen. ### 1.2.1 — 2026-07-29 Live-play polish and a few real fixes: • The dealer's hole card now stays hidden through split hands and multi-card hands until the round actually ends — just like a real table, instead of revealing after every graded decision. • "Continue after Hit" is now on by default, so hitting draws a real follow-up card instead of ending the hand early — and it now works on split hands too. • Drill preferences (Focus, Timed, session length, etc.) save the moment you change them, not just when you tap Start. • Fixed a rare case where a split hand's grading could disagree with the Strategy Chart's own reference for that exact hand. • Razor-thin decisions (like 16 vs. 10) now show a "Close call" tag explaining why Basis21's exact-cards math can occasionally read a hair differently than a generic printed chart — both options are essentially a coin flip. As always: perfect practice makes perfect basic strategy. ### 1.2 — 2026-07-23 Continue after Hit: turn it on in Drill Setup to draw one more real card after hitting and make a follow-up decision — the draw is controlled to never bust, so you actually play out the position instead of the hand ending the moment you hit. Sharper explanations: every "why" now speaks to the choice you actually made instead of a generic script, including clearer reasoning for when hitting beats doubling or surrendering. New drill modes: "Review mistakes" loops you through hands you've missed before; "Close calls" focuses drilling on the chart's genuine coin-flip decisions. Chart improvements: remembers where you left off when you jump back from Drill, and reads cleaner with new collapsed "Always Hit" and "Always Stand" rows. Accessibility: added a colorblind-friendly palette option in Settings. Plus a clearer basic-strategy primer and various small fixes. ### 1.1.1 — 2026-07-17 NEW: Strategy chart now marks Dh/Ds and Rh/Rs — cells where Double or Surrender is the best play but not always available show the right fallback (Hit or Stand) at a glance, matching real printed strategy cards. Explanations now call out when a table's own rules — a limited doubling range, or surrender withdrawn against an Ace — are the reason the better play isn't on the table, instead of glossing over it. Fixed: a custom profile copied from a preset could keep showing the original table's rule badge (e.g. still say H17 after you'd switched it to S17). Previously in 1.1: NEW: Compare any two tables side by side (Premium) — see the exact rule differences, each table's house edge, and exactly which hands change strategy, at a glance. Card back and felt color customization is back, with more options. Refined the rules on several casino presets (Singapore, Melbourne, Foxwoods) based on further research — always double-check against your actual table's posted rules. Smoother performance throughout. ## More apps by VINCENT WAH KIT WONG - [dian - Vocabulary Widget](https://appshunter.io/ios/app/dian-vocabulary-widget/id6782601294) All apps by VINCENT WAH KIT WONG: https://appshunter.io/developer/6782601296 --- *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 2026-08-03.*