# Data Structure Display vs 直接记

The clearest difference is price: Data Structure Display at Free against 直接记's $0.99. Data Structure Display also leads on review sentiment (62% vs 50%) and device support (4 vs 2). 直接记's advantage is in-app purchases (none vs 1) and update cadence (every 6 weeks vs every 5 months). On ads there is nothing between them.

Data Structure Display is free to download; 直接记 costs $0.99 up front. Data Structure Display sells 1 one-off in-app purchase. 直接记 asks for nothing beyond the download.

Data Structure Display ships an update every 5 months, 直接记 every 6 weeks. The most recent releases landed on October 13, 2026 and September 27, 2026 respectively.

## The numbers

| Metric | Data Structure Display | 直接记 |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | **[4.5 (676 ratings)](https://appshunter.io/ios/app/data-structure-display/id1455489695/reviews)** | — |
| Number of ratings | **676** | — |
| Positive reviews | **61.9% of reviews** | 50.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 6 weeks** |
| Monetization | Free with in-app purchases | — |
| Size | 8 MB | 36 MB |
| Requires iOS | **13.0** | 18.6 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Jinan Matrix Information Technology Co., Ltd.](https://appshunter.io/developer/1009091575) | [Chongqing Hyperits Network Technology Co., Ltd.](https://appshunter.io/developer/1866276929) |

## What reviewers say

### Data Structure Display

[App page](https://appshunter.io/ios/app/data-structure-display/id1455489695)

Explore and learn data structures through dynamic debugging and visual observation of changes. This app covers linear structures, trees, graphs, and recursive algorithms like the Tower of Hanoi, offering interactive learning experiences.

**Highlights:** Dynamic data structure debugging, Visual observation of data structure changes, Learn linear structures (arrays, lists, queues, stacks), Explore tree structures (binary, AVL, red-black, heap), Understand graph structures and algorithms, Debug recursive algorithms like Tower of Hanoi

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock all data structures | $2.99 | one-time |

**What reviewers like**

- 📚 Excellent for DSA learning and studying
- ✨ Interactive components and pseudo code quality
- 👍 Good reference material for beginners
- 🎓 Unique educational content

**What reviewers complain about**

- 🔒 90% of content locked behind $2.99 paywall
- 📖 Incomplete coverage of data structures
- ✍️ Poor grammar and spelling
- 📱 No dark mode support on macOS
- 🔔 Excessive review prompts

**Reported bugs**

- Aggressive review request frequency
- Inconsistent dark mode functionality between iOS and macOS

**Requested features**

- Dark mode implementation
- Comprehensive coverage of all data structure variants
- More practical exercises and problems
- Ad-supported free tier instead of paywall


### 直接记

[App page](https://appshunter.io/ios/app/id6759551391)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Data Structure Display free?

Data Structure Display is free to download, with in-app purchases available.

### Is 直接记 free?

直接记 costs $0.99, with no in-app purchases.

### Do Data Structure Display or 直接记 have ads?

Neither Data Structure Display nor 直接记 shows ads.

### Which is updated more often, Data Structure Display or 直接记?

Data Structure Display ships an update every 5 months, and 直接记 every 6 weeks. Most recently, Data Structure Display was updated on October 13, 2026 and 直接记 on September 27, 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.*