# 글씨21 vs Lesson On

The clearest difference is iOS requirement: 글씨21 at 11.0 against Lesson On's 17.6. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

글씨21 ships an update every 11 days, Lesson On weekly. The most recent releases landed on October 8, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | 글씨21 | Lesson On |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 11 days | **Weekly** |
| Size | 4 MB | 32 MB |
| Requires iOS | **11.0** | 17.6 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [TAEJIN SEOK](https://appshunter.io/developer/1222953416) | [Moon Su Choi](https://appshunter.io/developer/1888959670) |

## What reviewers say

### 글씨21

[App page](https://appshunter.io/ios/app/21/id1222953417)

**Features:** macOS Compatibility

**In-app purchases:** none


### Lesson On

[App page](https://appshunter.io/ios/app/lesson-on/id6761332046)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is 글씨21 free?

글씨21 is free to download, with no in-app purchases.

### Is Lesson On free?

Lesson On is free to download, with no in-app purchases.

### Do 글씨21 or Lesson On have ads?

Neither 글씨21 nor Lesson On shows ads.

### Which is updated more often, 글씨21 or Lesson On?

글씨21 ships an update every 11 days, and Lesson On weekly. Most recently, 글씨21 was updated on October 8, 2026 and Lesson On on September 28, 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.*