# ZeroOne Keyboard vs Flicker Insight

The clearest difference is price: ZeroOne Keyboard at Free against Flicker Insight's $0.99. ZeroOne Keyboard also leads on review sentiment (100% vs 60%) and ratings volume (5 vs 1). Flicker Insight's advantage is rating (5.0 vs 4.2) and update cadence (every 2 days vs every 4 days). On ads, in-app purchases and device support there is nothing between them.

ZeroOne Keyboard is free to download; Flicker Insight costs $0.99 up front. ZeroOne Keyboard sells 4 one-off in-app purchases and Flicker Insight sells 2 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Flicker Insight holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: ZeroOne Keyboard has 5 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 100% of ZeroOne Keyboard's written reviews are positive against 60% of Flicker Insight's, so the app with the better star average is not the one people write more warmly about.

ZeroOne Keyboard ships an update every 4 days, Flicker Insight every 2 days. The most recent releases landed on October 28, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | ZeroOne Keyboard | Flicker Insight |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | [4.2 (5 ratings)](https://appshunter.io/ios/app/zeroone-keyboard/id6757943442/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/flicker-insight-pwm-test/id6794661401/reviews)** |
| Number of ratings | **5** | 1 |
| Positive reviews | **100.0% of reviews** | 60.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 4 days | **Every 2 days** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 42 MB | 212 MB |
| Requires iOS | **16.0** | 18.0 |
| Devices | **iPhone, Mac** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [海平 吴](https://appshunter.io/developer/1011086237) | [名楷 王](https://appshunter.io/developer/1896763218) |

## What reviewers say

### ZeroOne Keyboard

[App page](https://appshunter.io/ios/app/zeroone-keyboard/id6757943442)

This keyboard app offers advanced Chinese shuangpin input with on-device processing for enhanced privacy. It features customizable schemes, emoji support, conversion tools, and theme syncing.

**Highlights:** Multiple shuangpin schemes, On-device data processing, Full Unicode emoji support, Math and unit conversions, Customizable themes, Local sync for themes and snippets

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| One Cup of Tea | $0.99 | one-time |
| Two Cups of Tea | $2.99 | one-time |
| Afternoon Tea | $3.99 | one-time |
| 01+ Lifetime Supporter | $9.99 | one-time |


### Flicker Insight

[App page](https://appshunter.io/ios/app/flicker-insight-pwm-test/id6794661401)

Detects imperceptible light flicker from various sources like screens and bulbs that can cause eye strain. Offers detailed metrics, ambient light and color temperature estimates, and generates exportable reports. Prioritizes user privacy with offline functionality and no ads.

**Highlights:** Quick flicker test with camera, Eye comfort assessment, Detailed flicker metrics, Ambient illuminance estimate, Color temperature estimate, PDF report generation, Offline functionality

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| A Popsicle | $0.99 | one-time |
| A Coffee | $2.99 | one-time |


## Frequently asked questions

### Is ZeroOne Keyboard free?

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

### Is Flicker Insight free?

Flicker Insight costs $0.99, and also offers in-app purchases.

### Which has better reviews, ZeroOne Keyboard or Flicker Insight?

Flicker Insight is rated higher. ZeroOne Keyboard averages 4.2 out of 5 from 5 ratings, while Flicker Insight averages 5.0 from 1 ratings.

### Do ZeroOne Keyboard or Flicker Insight have ads?

Neither ZeroOne Keyboard nor Flicker Insight shows ads.

### Which is updated more often, ZeroOne Keyboard or Flicker Insight?

ZeroOne Keyboard ships an update every 4 days, and Flicker Insight every 2 days. Most recently, ZeroOne Keyboard was updated on October 28, 2026 and Flicker Insight on October 29, 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.*