# DOGTOR 逗課 vs Kernel 背單字

The clearest difference is in-app purchases: Kernel 背單字 at none against DOGTOR 逗課's 2. DOGTOR 逗課's advantage is iOS requirement (15.0 vs 17.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. DOGTOR 逗課 sells 2 in-app purchases, starting at $9.99 per month. Kernel 背單字 asks for nothing beyond the download.

DOGTOR 逗課 ships an update every 10 days, Kernel 背單字 weekly. The most recent releases landed on September 10, 2026 and September 19, 2026 respectively.

## The numbers

| Metric | DOGTOR 逗課 | Kernel 背單字 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Every 10 days | **Weekly** |
| Size | 151 MB | 63 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Bohua Chen](https://appshunter.io/developer/1814880685) | [Egan Bisma](https://appshunter.io/developer/1882424495) |

## What reviewers say

### DOGTOR 逗課

[App page](https://appshunter.io/ios/app/dogtor/id6751773627)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| DOGTOR PRO 月度專業版 | $9.99 | per month |
| DOGTOR PRO 年度專業版 | $99.99 | per year |


### Kernel 背單字

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

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

**In-app purchases:** none


## Frequently asked questions

### Is DOGTOR 逗課 free?

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

### Is Kernel 背單字 free?

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

### Do DOGTOR 逗課 or Kernel 背單字 have ads?

Both DOGTOR 逗課 and Kernel 背單字 show ads.

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

DOGTOR 逗課 ships an update every 10 days, and Kernel 背單字 weekly. Most recently, DOGTOR 逗課 was updated on September 10, 2026 and Kernel 背單字 on September 19, 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.*