# LogicSystem vs Lux Light Meter

The clearest difference is in-app purchases: LogicSystem at none against Lux Light Meter's 3. LogicSystem also leads on iOS requirement (15.0 vs 17). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Lux Light Meter sells 3 in-app purchases, starting at $1.99 per 7 days. LogicSystem asks for nothing beyond the download.

LogicSystem ships an update every 2 weeks, Lux Light Meter fortnightly. The most recent releases landed on October 11, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | LogicSystem | Lux Light Meter |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (5 ratings)](https://appshunter.io/ios/app/lux-light-meter-illuminance/id6790679680/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Fortnightly** |
| Monetization | — | Free with in-app purchases |
| Size | 57 MB | 4 MB |
| Requires iOS | **15.0** | 17 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [HST Innovations LLC](https://appshunter.io/developer/670745958) | [灿耿 陈](https://appshunter.io/developer/1688324562) |

## What reviewers say

### LogicSystem

[App page](https://appshunter.io/ios/app/logicsystem/id6753318710)

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

**In-app purchases:** none


### Lux Light Meter

[App page](https://appshunter.io/ios/app/lux-light-meter-illuminance/id6790679680)

Measure ambient light levels with your iPhone. Get real-time lux and foot-candle readings, with specialized modes for photography and plant care. Track light history and calibrate for accuracy.

**Highlights:** Ambient light metering (lux/fc), Photography exposure suggestions, Plant light (PPFD/DLI) estimation, Continuous measurement and history, Optional meter calibration, Privacy-friendly local storage

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Access | $1.99 | per 7 days |
| Annual Subscription | $7.99 | per year |
| Lifetime Access | $4.99 | one-time |


## Frequently asked questions

### Is LogicSystem free?

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

### Is Lux Light Meter free?

Lux Light Meter is free to download, with in-app purchases available.

### Do LogicSystem or Lux Light Meter have ads?

Neither LogicSystem nor Lux Light Meter shows ads.

### Which is updated more often, LogicSystem or Lux Light Meter?

LogicSystem ships an update every 2 weeks, and Lux Light Meter fortnightly. Most recently, LogicSystem was updated on October 11, 2026 and Lux Light Meter on October 8, 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.*