# Turn Light On vs ReactionTimeChecker

The clearest difference is ads: Turn Light On at none against ReactionTimeChecker's shown. Turn Light On also leads on update cadence (every 5 weeks vs every 7 months) and iOS requirement (12.1 vs 15.6). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Turn Light On ships an update every 5 weeks, ReactionTimeChecker every 7 months. The most recent releases landed on October 11, 2026 and October 23, 2026 respectively.

## The numbers

| Metric | Turn Light On | ReactionTimeChecker |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[1.0 (1 ratings)](https://appshunter.io/ios/app/reactiontimechecker/id537191082/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 33.3% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Every 5 weeks** | Every 7 months |
| Monetization | — | Ad-supported |
| Size | 15 MB | 22 MB |
| Requires iOS | **12.1** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Giuseppe Calcagno](https://appshunter.io/developer/510762783) | [NSC, K.K.](https://appshunter.io/developer/501890400) |

## What reviewers say

### Turn Light On

[App page](https://appshunter.io/ios/app/turn-light-on/id519685020)

**In-app purchases:** none


### ReactionTimeChecker

[App page](https://appshunter.io/ios/app/reactiontimechecker/id537191082)

Test your reflexes by tapping a color-changing button as quickly as possible. Compete with others through online leaderboards and receive an evaluation of your performance.

**Highlights:** Reaction time testing, Color-changing button gameplay, Score and evaluation display, Online ranking system, Automatic result upload

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Turn Light On free?

Turn Light On is free to download, with no in-app purchases.

### Is ReactionTimeChecker free?

ReactionTimeChecker is free to download, with no in-app purchases.

### Do Turn Light On or ReactionTimeChecker have ads?

ReactionTimeChecker shows ads; Turn Light On does not.

### Which is updated more often, Turn Light On or ReactionTimeChecker?

Turn Light On ships an update every 5 weeks, and ReactionTimeChecker every 7 months. Most recently, Turn Light On was updated on October 11, 2026 and ReactionTimeChecker on October 23, 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.*