# The Letter Flash Machine vs Subtraction Mathematics

The clearest difference is price: Subtraction Mathematics at Free against The Letter Flash Machine's $0.99. Subtraction Mathematics also leads on update cadence (fortnightly vs every 31 months) and ratings volume (28 vs 1). The Letter Flash Machine's advantage is rating (5.0 vs 4.2) and in-app purchases (none vs 1). On ads and device support there is nothing between them.

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

The Letter Flash Machine holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: Subtraction Mathematics has 28 ratings behind it against 1, so its average is the more settled of the two.

The Letter Flash Machine ships an update every 31 months, Subtraction Mathematics fortnightly. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | The Letter Flash Machine | Subtraction Mathematics |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/the-letter-flash-machine/id1005102385/reviews)** | [4.2 (28 ratings)](https://appshunter.io/ios/app/subtraction-mathematics/id1660955330/reviews) |
| Number of ratings | 1 | **28** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 31 months | **Fortnightly** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 15 MB | 172 MB |
| Requires iOS | **12.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Ventura Educational Systems](https://appshunter.io/developer/371324172) | [PROGRAMIS PRIME LLC](https://appshunter.io/developer/1051843545) |

## What reviewers say

### The Letter Flash Machine

[App page](https://appshunter.io/ios/app/the-letter-flash-machine/id1005102385)

This app helps young children learn to recognize alphabet letters through interactive keyboard matching and picture-based letter identification. It tracks performance and uses sound effects to enhance the learning experience.

**Highlights:** Letter recognition games, Keyboard matching activity, Picture-based letter identification, Performance tracking, Pronouncing letters, Sound effects for engagement

**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 The Letter Flash Machine free?

The Letter Flash Machine costs $0.99, with no in-app purchases.

### Is Subtraction Mathematics free?

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

### Which has better reviews, The Letter Flash Machine or Subtraction Mathematics?

The Letter Flash Machine is rated higher. The Letter Flash Machine averages 5.0 out of 5 from 1 ratings, while Subtraction Mathematics averages 4.2 from 28 ratings.

### Do The Letter Flash Machine or Subtraction Mathematics have ads?

Neither The Letter Flash Machine nor Subtraction Mathematics shows ads.

### Which is updated more often, The Letter Flash Machine or Subtraction Mathematics?

The Letter Flash Machine ships an update every 31 months, and Subtraction Mathematics fortnightly. Most recently, The Letter Flash Machine was updated on November 1, 2026 and Subtraction Mathematics on November 3, 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.*