Four By 21
Alexander Harm Games iPhoneiPadiPod touch
Four By 21 is a free Games app for iPhone and iPad by Alexander Harm. Requires iOS 15.6. Updated May 17, 2026.
- Price
- Free
- on the App Store
- Size
- 22 MB
- Age 4+
- Updated
- May 17
- 2026 · v2.1
Screenshots
About 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.
What’s new
Version 2.1 · Updated May 17, 2026
Sound effects adjustments
Play today's Frostfire puzzle
Balance fire and ice: half of each in every row and column. A free daily puzzle from Fiplay, same board for everyone. It plays right here, no download.
App privacy
The developer, Alexander Harm, reported these privacy practices to Apple.
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers: Device ID
- Usage Data: Product Interaction, Advertising Data
- Diagnostics: Crash Data, Performance Data
Data Linked to You
The following data, which may be collected and linked to your identity, may be used for the following purposes:
- Identifiers: Device ID
- Usage Data: Product Interaction, Advertising Data
- Diagnostics: Performance Data
Used for: Third-Party Advertising, Analytics
Data Not Linked to You
The following data, which may be collected but is not linked to your identity, may be used for the following purposes:
- Diagnostics: Crash Data
Used for: Third-Party Advertising, Analytics
Alternatives to Four By 21
Looking for apps like Four By 21? Here are 6 similar apps on the App Store. The highest rated is Rush To 21 (5.0/5), and all 6 are free to download.
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Blitz21: Fast Card Puzzle
| App | Rating | Price | Last updated | Compare |
|---|---|---|---|---|
| Four By 21 | – | Free | May 17, 2026 | |
| 21 Turbo Blitz | 3.8 / 5 (4) | Free | May 9, 2025 | Compare |
| Rush To 21 | 5.0 / 5 (6) | Free | Jan 8, 2026 | Compare |
| Cards 21 - Puzzle Card Game | – | Free | Oct 15, 2025 | Compare |
| Heart Supreme Blackjack21 | 4.4 / 5 (37) | Free | Jun 12, 2026 | Compare |
| Penny’s 21: Retro Blackjack | 5.0 / 5 (1) | Free | Oct 20, 2026 | Compare |
| Blitz21: Fast Card Puzzle | – | Free | Apr 22, 2026 | Compare |
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