# Four By 21 — Fast-Paced Card Game

> Fast-Paced Card Game (iPhone/iPad app by Alexander Harm.)

- Source: https://appshunter.io/ios/app/four-by-21/id1501220469 (this page in markdown: same URL + `.md`)
- Developer: [Alexander Harm](https://appshunter.io/developer/1012507990)
- Category: Games, Card
- Price: Free
- Age rating: 4+
- Requires: iOS 15.6 · 22 MB
- Languages: English
- Released: 2020-03-04
- Data updated: 2026-05-22
- User reviews in markdown: https://appshunter.io/ios/app/four-by-21/id1501220469/reviews.md

## What is Four By 21?

Four columns. One goal: 21.

Four By 21 is a fast-paced card puzzle where blackjack strategy meets solitaire. Stack cards into four columns, make 21, clear space, and race the clock.

Use HOLD wisely, build streaks, and chase high scores without busting.

How to Play

- Place Your Cards: Tap one of the four columns to place your active card.
- Reach 21: Make a column total exactly 21 to clear it and score points. Aces count as 1 or 11, and face cards count as 10.
- Watch the Busts: If a column goes over 21, you bust. You only get 5 busts per round before it is game over.
- Beat the Clock: You start with 70 seconds. Every time you clear a column, you earn bonus time to keep the game alive.

Key Features and Scoring Strategies

- The Hold Slot: Tap the Hold zone to save your active card for later. Swap it out when the right moment arrives to save a column or score a combo.
- Streak Multipliers: Chain together rapid clears without mistakes to build your streak multiplier and drive up your score.
- 5-Card Charlie: Play five cards in a single column without busting to clear it instantly for a 600-point reward.
- Lucky 7-7-7: Stack three 7s to hit 21 and earn a 400-point bonus.
- Board Clear Bonus: Clear all four columns to sweep the board and trigger a big score boost.


## Version history (last 5 releases)

### 2.1 — 2026-05-17

Sound effects adjustments

### 2.0 — 2026-04-18

- Redesigned layout throughout the game
- All-new animations
- Updated graphics
- New sounds
- Updated scoring

### 1.3 — 2021-03-20

Third Party API update
Countdown timer bug fix
Layout fix for iPhone 11
Layout adjustments for third-party elements

### 1.2 — 2020-10-21

iPhone 12 & iOS 14 support
Third Party API updates

### 1.1 — 2020-06-14

3rd Party Library Updates
Launch Screen Update

## Apps similar to Four By 21

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Zero21 Card Game](https://appshunter.io/ios/app/zero21-card-game/id1550265606) | 4.0 (3) | Free | Games |
| [Rush To 21](https://appshunter.io/ios/app/rush-to-21/id1035427299) | 5.0 (5) | Free | Games |
| [Catch 21 Multiplayer Solitaire](https://appshunter.io/ios/app/catch-21-multiplayer-solitaire/id1537764039) | — | Free | Games |
| [Puzzle 21 - Card Challenge](https://appshunter.io/ios/app/puzzle-21-card-challenge/id1474776973) | 4.8 (54) | Free | Games |
| [Grid Poker](https://appshunter.io/ios/app/grid-poker/id1573762498) | 4.5 (11) | Free | Games |
| [Zone 21 - Fast Math Solitaire](https://appshunter.io/ios/app/zone-21-fast-math-solitaire/id1484296990) | 4.8 (23) | Free | Games |

## More apps by Alexander Harm

- [Pressed For Words](https://appshunter.io/ios/app/pressed-for-words/id1012507991)
- [Searched For Words](https://appshunter.io/ios/app/searched-for-words/id1489896856)
- [Swiped For Words](https://appshunter.io/ios/app/swiped-for-words/id1598978182)

All apps by Alexander Harm: https://appshunter.io/developer/1012507990

---

*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 2026-05-22.*