# Clock Challenge vs Subtraction Mathematics

The clearest difference is price: Subtraction Mathematics at Free against Clock Challenge's $0.99. Subtraction Mathematics also leads on update cadence (fortnightly vs every 15 months). Clock Challenge's advantage is in-app purchases (none vs 1) and iOS requirement (14.2 vs 16.0). On ads and device support there is nothing between them.

Subtraction Mathematics is free to download; Clock Challenge costs $0.99 up front. Subtraction Mathematics sells 1 one-off in-app purchase. Clock Challenge asks for nothing beyond the download.

Clock Challenge ships an update every 15 months, Subtraction Mathematics fortnightly. The most recent releases landed on October 18, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Clock Challenge | Subtraction Mathematics |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | — | **[4.3 (27 ratings)](https://appshunter.io/ios/app/subtraction-mathematics/id1660955330/reviews)** |
| Number of ratings | — | **27** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 15 months | **Fortnightly** |
| Monetization | — | Free with in-app purchases |
| Size | 59 MB | 172 MB |
| Requires iOS | **14.2** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Jariya Tuantranont](https://appshunter.io/developer/404509814) | [PROGRAMIS PRIME LLC](https://appshunter.io/developer/1051843545) |

## What reviewers say

### Clock Challenge

[App page](https://appshunter.io/ios/app/clock-challenge/id597084739)

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

**In-app purchases:** none


### Subtraction Mathematics

[App page](https://appshunter.io/ios/app/subtraction-mathematics/id1660955330)

This math app teaches children multi-digit subtraction with step-by-step guidance and positive reinforcement. It adapts to the student's learning pace, offering practice for beginners and review for older students. Features include AI handwriting recognition and progress monitoring for parents and teachers.

**Highlights:** Multi-digit subtraction with borrowing, Step-by-step instructions, AI handwriting recognition, Progress monitoring with color-coded feedback, Customizable digit combinations, Encouragement-based learning

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Get All Features | $3.99 | one-time |


## Frequently asked questions

### Is Clock Challenge free?

Clock Challenge costs $0.99, with no in-app purchases.

### Is Subtraction Mathematics free?

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

### Do Clock Challenge or Subtraction Mathematics have ads?

Neither Clock Challenge nor Subtraction Mathematics shows ads.

### Which is updated more often, Clock Challenge or Subtraction Mathematics?

Clock Challenge ships an update every 15 months, and Subtraction Mathematics fortnightly. Most recently, Clock Challenge was updated on October 18, 2026 and Subtraction Mathematics on October 24, 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.*