# Light Meter LM vs 理控杆

The clearest difference is in-app purchases: 理控杆 at none against Light Meter LM's 3. 理控杆 also leads on update cadence (fortnightly vs monthly) and iOS requirement (12.0 vs 15.0). On price, ads and device support there is nothing between them.

Both are free to download. Light Meter LM sells 3 in-app purchases, starting at $3.49 per month. 理控杆 asks for nothing beyond the download.

Light Meter LM ships an update monthly, 理控杆 fortnightly. The most recent releases landed on November 11, 2026 and November 8, 2026 respectively.

## The numbers

| Metric | Light Meter LM | 理控杆 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (2.6K ratings)](https://appshunter.io/ios/app/light-meter-lm-3000/id1554264761/reviews)** | — |
| Number of ratings | **2.6K** | — |
| Positive reviews | 40.4% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Monthly | **Fortnightly** |
| Monetization | Free with in-app purchases | — |
| Size | 22 MB | 172 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Lightray Innovation GmbH](https://appshunter.io/developer/1031383431) | [南京理工科技系统有限公司](https://appshunter.io/developer/972965020) |

## What reviewers say

### Light Meter LM

[App page](https://appshunter.io/ios/app/light-meter-lm-3000/id1554264761)

Transform your smartphone into a professional light meter. Measure illuminance and color temperature with scientifically validated accuracy, trusted by professionals. Requires a simple diffuser for precise readings.

**Highlights:** Measure illuminance (lux/foot-candle), Measure color temperature (Kelvin), Industry-leading accuracy, Pre-calibrated for your device, Low light sensitivity, Save peak reading, Custom calibration option

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Continuous Charging | $3.49 | per month |
| Single Charge | $0.99 | one-time |
| Unlimited Battery | $19.99 | one-time |

**What reviewers like**

- 👍 Great app
- 👍 Accurate measurements
- 👍 Easy to use
- 👍 Helpful customer service
- 👍 Useful for science/research

**What reviewers complain about**

- 🐛 Requires diffuser for accurate readings
- 💰 Expensive for a light meter app
- 🔋 Battery/trial period issues
- 🔍 Inconsistent/inaccurate readings
- 🙄 Misleading/deceptive marketing

**Reported bugs**

- Diffuser not recognized even when used
- App locks up/crashes
- Constant diffuser pop-up interruptions

**Requested features**

- Ability to use rear camera
- More flexible diffuser options
- Improved accuracy without diffuser


### 理控杆

[App page](https://appshunter.io/ios/app/id6475380814)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Light Meter LM free?

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

### Is 理控杆 free?

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

### Do Light Meter LM or 理控杆 have ads?

Neither Light Meter LM nor 理控杆 shows ads.

### Which is updated more often, Light Meter LM or 理控杆?

Light Meter LM ships an update monthly, and 理控杆 fortnightly. Most recently, Light Meter LM was updated on November 11, 2026 and 理控杆 on November 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.*