# Abacus Lesson vs Flash Mental Math

The clearest difference is in-app purchases: Flash Mental Math at none against Abacus Lesson's 3. Abacus Lesson's advantage is update cadence (every 3 weeks vs every 3 months) and ratings volume (836 vs 19). On price, rating, review sentiment and ads there is nothing between them.

Both are free to download. Abacus Lesson sells 3 one-off in-app purchases. Flash Mental Math asks for nothing beyond the download.

Abacus Lesson holds the better App Store score, 4.9 against 4.7. That said, the two scores are not equally well evidenced: Abacus Lesson has 836 ratings behind it against 19, so its average is the more settled of the two. Written reviews complicate that: 93% of Abacus Lesson's written reviews are positive against 100% of Flash Mental Math's, so the app with the better star average is not the one people write more warmly about.

Abacus Lesson ships an update every 3 weeks, Flash Mental Math every 3 months. The most recent releases landed on October 29, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | Abacus Lesson | Flash Mental Math |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (836 ratings)](https://appshunter.io/ios/app/abacus-lesson-add-and-sub/id1526785916/reviews)** | [4.7 (19 ratings)](https://appshunter.io/ios/app/flash-mental-math-simple/id1547944841/reviews) |
| Number of ratings | **836** | 19 |
| Positive reviews | 93.1% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | **Every 3 weeks** | Every 3 months |
| Monetization | Free with in-app purchases | **Ad-supported** |
| Size | 138 MB | 14 MB |
| Requires iOS | **11.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Hirokazu Komatsu](https://appshunter.io/developer/1523833531) | [Ryouhei Azuma](https://appshunter.io/developer/1353297781) |

## What reviewers say

### Abacus Lesson

[App page](https://appshunter.io/ios/app/abacus-lesson-add-and-sub/id1526785916)

Learn addition and subtraction using a virtual abacus, also known as a Soroban. This app helps you develop mental calculation skills, enabling you to perform calculations without physical tools.

**Highlights:** Learn addition, Learn subtraction, Virtual abacus (Soroban), Develop mental calculation skills, Perform calculations without physical tools

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Donation Lv1 for hiding Ad | $1.99 | one-time |
| Donation Lv2 for hiding Ad | $3.99 | one-time |
| Donation Lv3 for hiding Ad | $8.99 | one-time |

**What reviewers like**

- 👍 Beginner-friendly and easy to use
- 🚀 Quick to learn basic concepts
- 📚 Clear and simple explanations
- 🎯 Effective teaching methodology
- 💰 Free with no ads

**What reviewers complain about**

- 🌐 Poor English translation quality
- 📖 Lessons sometimes hard to read
- ❌ Cannot skip levels
- ⚡ Difficulty progression too steep
- 🐛 App closes accidentally on iPhone when swiping

**Reported bugs**

- Accidental app closure on iPhone during bead swiping
- Error in lesson 3 addition summary
- Sloppy English translation causing confusion
- Lessons difficult to read visually

**Requested features**

- Add Chinese Abacus (Suanpan) option
- Landscape view support
- Level skip functionality
- Better English translation/editing
- Clearer problem presentation with equation format


### Flash Mental Math

[App page](https://appshunter.io/ios/app/flash-mental-math-simple/id1547944841)

Practice mental arithmetic with various difficulty levels and custom modes. This app serves as a brain training tool to enhance calculation skills.

**Highlights:** Mental arithmetic practice, Easy, normal, and difficult modes, Customizable modes, Brain training, Calculation skill improvement

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

**In-app purchases:** none


## Frequently asked questions

### Is Abacus Lesson free?

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

### Is Flash Mental Math free?

Flash Mental Math is free to download, with no in-app purchases.

### Which has better reviews, Abacus Lesson or Flash Mental Math?

Abacus Lesson is rated higher. Abacus Lesson averages 4.9 out of 5 from 836 ratings, while Flash Mental Math averages 4.7 from 19 ratings.

### Do Abacus Lesson or Flash Mental Math have ads?

Both Abacus Lesson and Flash Mental Math show ads.

### Which is updated more often, Abacus Lesson or Flash Mental Math?

Abacus Lesson ships an update every 3 weeks, and Flash Mental Math every 3 months. Most recently, Abacus Lesson was updated on October 29, 2026 and Flash Mental Math on October 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.*