# Kernel 背單字 vs SparkGlow

The clearest difference is in-app purchases: Kernel 背單字 at none against SparkGlow's 4. Kernel 背單字 also leads on update cadence (weekly vs fortnightly). SparkGlow's advantage is ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. SparkGlow sells 4 in-app purchases, starting at $2.99 per month. Kernel 背單字 asks for nothing beyond the download.

Kernel 背單字 ships an update weekly, SparkGlow fortnightly. The most recent releases landed on October 3, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Kernel 背單字 | SparkGlow |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | **Weekly** | Fortnightly |
| Size | 63 MB | 31 MB |
| Requires iOS | **17.0** | 17.2 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Egan Bisma](https://appshunter.io/developer/1882424495) | [Yu Chen Huang](https://appshunter.io/developer/6793047805) |

## 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


### SparkGlow

[App page](https://appshunter.io/ios/app/sparkglow/id6793047803)

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| SparkGlow Pro Monthly | $2.99 | per month |
| SparkGlow Max Monthly | $4.99 | per month |
| SparkGlow Pro Yearly | $29.99 | per year |
| SparkGlow Max Yearly | $39.99 | 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 SparkGlow free?

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

### Do Kernel 背單字 or SparkGlow have ads?

Kernel 背單字 shows ads; SparkGlow does not.

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

Kernel 背單字 ships an update weekly, and SparkGlow fortnightly. Most recently, Kernel 背單字 was updated on October 3, 2026 and SparkGlow on October 14, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*