# Kernel 背單字 vs Tomaru

The clearest difference is in-app purchases: Kernel 背單字 at none against Tomaru's 6. Kernel 背單字 also leads on update cadence (weekly vs monthly). Tomaru's advantage is ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Tomaru sells 6 in-app purchases, starting at $5.99 per month. Kernel 背單字 asks for nothing beyond the download.

Kernel 背單字 ships an update weekly, Tomaru monthly. The most recent releases landed on October 3, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Kernel 背單字 | Tomaru |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/tomaru-never-forget-a-word/id6765955927/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | **Weekly** | Monthly |
| Monetization | — | Free with in-app purchases |
| Size | 63 MB | 126 MB |
| Requires iOS | 17.0 | **16.4** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Egan Bisma](https://appshunter.io/developer/1882424495) | [YINGLUEN TSENG](https://appshunter.io/developer/1896139802) |

## What reviewers say

### Kernel 背單字

[App page](https://appshunter.io/ios/app/kernel/id6760036064)

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

**In-app purchases:** none


### Tomaru

[App page](https://appshunter.io/ios/app/tomaru-never-forget-a-word/id6765955927)

This app uses spaced repetition and AI-powered practice to help you effectively learn and retain new vocabulary. It offers pre-made decks, one-tap vocabulary import from various sources, and immersive focus features.

**Highlights:** Spaced repetition system (FSRS algorithm), Pre-made vocabulary decks with rich content, One-tap vocabulary import from text, AI-powered shadowing, translation, and grammar drills, Immersive focus with ambient sounds

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tensai Basic Monthly Subscription | $5.99 | per month |
| Tensai Basic Quarterly Subscription | $14.99 | per 3 months |
| Tensai PRO Monthly Subscription | $15.90 | per month |
| Tensai PRO Quarterly Subscription | $44.99 | per 3 months |
| Tensai Basic Annual Subscription | $49.99 | per year |
| Tensai PRO Annual | $169.99 | per year |


## Frequently asked questions

### Is Kernel 背單字 free?

Kernel 背單字 is free to download, with no in-app purchases.

### Is Tomaru free?

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

### Do Kernel 背單字 or Tomaru have ads?

Kernel 背單字 shows ads; Tomaru does not.

### Which is updated more often, Kernel 背單字 or Tomaru?

Kernel 背單字 ships an update weekly, and Tomaru monthly. Most recently, Kernel 背單字 was updated on October 3, 2026 and Tomaru on October 12, 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.*