# 21 Trainer vs Blackjack Counting

The clearest difference is rating: Blackjack Counting at 4.1 against 21 Trainer's 3.4. 21 Trainer's advantage is update cadence (every 5 days vs every 31 months) and iOS requirement (9.0 vs 16.0). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Blackjack Counting holds the better App Store score, 4.1 against 3.4. Both are backed by a comparable volume of ratings — 20 and 38 respectively.

21 Trainer ships an update every 5 days, Blackjack Counting every 31 months. The most recent releases landed on June 7, 2026 and September 20, 2026 respectively.

## The numbers

| Metric | 21 Trainer | Blackjack Counting |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.4 (20 ratings)](https://appshunter.io/ios/app/21-trainer/id1309810444/reviews) | **[4.1 (38 ratings)](https://appshunter.io/ios/app/blackjack-counting/id1544949227/reviews)** |
| Number of ratings | 20 | **38** |
| Positive reviews | 53.8% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 5 days** | Every 31 months |
| Monetization | Free | Free |
| Size | 37 MB | 4 MB |
| Requires iOS | **9.0** | 16.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 17+ | 4+ |
| Developer | [Bulletproof Entertainment](https://appshunter.io/developer/1309810443) | [Tomoki Tsukiyama](https://appshunter.io/developer/1493558845) |

## What reviewers say

### 21 Trainer

[App page](https://appshunter.io/ios/app/21-trainer/id1309810444)

Practice card counting to improve your blackjack skills. Challenge yourself to count as many cards as possible within a 30-second time limit.

**Highlights:** Card counting practice, 30-second challenges, Blackjack game improvement, Beat the dealer strategy

**Features:** macOS Compatibility

**In-app purchases:** none


### Blackjack Counting

[App page](https://appshunter.io/ios/app/blackjack-counting/id1544949227)

Learn to count cards for blackjack with this easy-to-use application. Master the game and improve your odds at the casino.

**Highlights:** Easy card counting, Blackjack strategy training, Improve odds, Casino game practice

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is 21 Trainer free?

21 Trainer is free to download, with no in-app purchases.

### Is Blackjack Counting free?

Blackjack Counting is free to download, with no in-app purchases.

### Which has better reviews, 21 Trainer or Blackjack Counting?

Blackjack Counting is rated higher. 21 Trainer averages 3.4 out of 5 from 20 ratings, while Blackjack Counting averages 4.1 from 38 ratings.

### Do 21 Trainer or Blackjack Counting have ads?

Neither 21 Trainer nor Blackjack Counting shows ads.

### Which is updated more often, 21 Trainer or Blackjack Counting?

21 Trainer ships an update every 5 days, and Blackjack Counting every 31 months. Most recently, 21 Trainer was updated on June 7, 2026 and Blackjack Counting on September 20, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*