# Pengword vs Kusari

The clearest difference is update cadence: Pengword at every 3 days against Kusari's every 10 days. Kusari's advantage is iOS requirement (15.1 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Pengword sells 1 in-app purchase, starting at $2.99 per month and Kusari sells 1 in-app purchase, starting at $29.99 per month. Whichever you choose, the download price is not the number that matters.

Pengword ships an update every 3 days, Kusari every 10 days. The most recent releases landed on November 9, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Pengword | Kusari |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 3 days** | Every 10 days |
| Monetization | — | Free with in-app purchases |
| Size | 26 MB | 123 MB |
| Requires iOS | 26.0 | **15.1** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Toya Niibori](https://appshunter.io/developer/1576276952) | [RYUTA ABE](https://appshunter.io/developer/1895880547) |

## What reviewers say

### Pengword

[App page](https://appshunter.io/ios/app/pengword-fun-word-learning/id6761671432)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Monthly | $2.99 | per month |


### Kusari

[App page](https://appshunter.io/ios/app/kusari/id6764690812)

This app uses behavioral economics to build a daily English learning habit. It employs a commitment device where users risk losing money if they miss their daily tasks, encouraging consistent practice through financial stakes rather than willpower. Daily activities include reading, shadowing, and AI conversation, taking 15-20 minutes.

**Highlights:** Commitment device with financial stakes, Daily reading, shadowing, and AI conversation, 15-20 minute daily tasks, Behavioral economics principles applied, Dynamic skill level adjustment (CEFR A1-C2), Tiered pricing based on daily achievement

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Kusari Monthly | $29.99 | per month |


## Frequently asked questions

### Is Pengword free?

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

### Is Kusari free?

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

### Do Pengword or Kusari have ads?

Neither Pengword nor Kusari shows ads.

### Which is updated more often, Pengword or Kusari?

Pengword ships an update every 3 days, and Kusari every 10 days. Most recently, Pengword was updated on November 9, 2026 and Kusari on October 31, 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.*