# Delta vs 试题库

The clearest difference is in-app purchases: 试题库 at none against Delta's 3. Delta's advantage is update cadence (monthly vs every 3 months) and device support (4 vs 1). On price and ads there is nothing between them.

Both are free to download. Delta sells 3 one-off in-app purchases. 试题库 asks for nothing beyond the download.

Delta ships an update monthly, 试题库 every 3 months. The most recent releases landed on August 19, 2026 and September 13, 2026 respectively.

## The numbers

| Metric | Delta | 试题库 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.1 (7 ratings)](https://appshunter.io/ios/app/delta-algorithms/id1436506800/reviews)** | — |
| Number of ratings | **7** | — |
| Positive reviews | 66.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Monthly** | Every 3 months |
| Monetization | Freemium | — |
| Size | 5 MB | 18 MB |
| Requires iOS | **13.0** | 17 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [Groupe MINASTE](https://appshunter.io/developer/1378426984) | [中科软股教育科技(北京)股份有限公司](https://appshunter.io/developer/1395665821) |

## What reviewers say

### Delta

[App page](https://appshunter.io/ios/app/delta-algorithms/id1436506800)

This app helps users solve math problems by creating and executing algorithms. It offers tools for homework checking, test preparation, and creating custom quizzes. Users can save, share, and download algorithms via the cloud.

**Highlights:** Create algorithms with natural language, Execute algorithms to solve math problems, Create and download custom quizzes, Save and share algorithms, Cloud synchronization for algorithms

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Donation 1 | $0.99 | one-time |
| Donation 2 | $2.99 | one-time |
| Donation 3 | $4.99 | one-time |


### 试题库

[App page](https://appshunter.io/ios/app/id1478850740)

**In-app purchases:** none


## Frequently asked questions

### Is Delta free?

Delta is free to download, with in-app purchases available.

### Is 试题库 free?

试题库 is free to download, with no in-app purchases.

### Do Delta or 试题库 have ads?

Neither Delta nor 试题库 shows ads.

### Which is updated more often, Delta or 试题库?

Delta ships an update monthly, and 试题库 every 3 months. Most recently, Delta was updated on August 19, 2026 and 试题库 on September 13, 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.*