# Light Meter LM-3000 — Simple & accurate measurement!

> Smartphone light meter app measuring illuminance and color temperature. (iPhone/iPad app by Lightray Innovation GmbH.)

- Source: https://appshunter.io/ios/app/light-meter-lm-3000/id1554264761 (this page in markdown: same URL + `.md`)
- Developer: [Lightray Innovation GmbH](https://appshunter.io/developer/1031383431)
- Category: Utilities
- Price: Free with in-app purchases
- Rating: 4.50/5 from 2,547 App Store ratings · 200 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.0 · 22 MB
- Languages: German (Germany), European Spanish, American English, Italian, Japanese, Chinese (Simplified, China), Chinese (Traditional, Taiwan), French (France)
- Released: 2021-03-09
- Data updated: 2026-08-27
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/light-meter-lm-3000/id1554264761/reviews.md

## What is Light Meter LM?

Turn your smartphone into a professional-grade light meter. Measure illuminance (lux/foot-candle) and color temperature (CCT in Kelvin) with unmatched accuracy — trusted by photographers, engineers, and lighting professionals worldwide.

Why waste money on a hardware meter when you’re already carrying one in your pocket?

The LM-3000 offers the same quality and usability as a traditional hardware light meter.
Developed by optics scientists at the Zurich University of Applied Sciences, LM-3000 is the only light meter app scientifically validated for accuracy. It achieves professional-grade precision by leveraging your iPhone's front-facing camera sensor with advanced RAW image processing. Unlike relying on estimates like other apps, it adheres to the ISO/CIE 19476 standard, ensuring measurements you can trust for critical applications.

MEASUREMENTS

⎷ Illuminance in lux or foot-candles
⎷ Correlated color temperature in kelvin

FEATURES

⎷ Industry-leading accuracy, matching professional high-end lux meters
⎷ Pre-calibrated for your specific device
⎷ Excellent low light sensitivity to detect light pollution
⎷ No ads
⎷ No Bluetooth and location permission required
⎷ In-app manual
⎷ Save peak reading
⎷ HOLD function with acoustic signal
⎷ Custom calibration option to align readings to another meter

DIFFUSER REQUIRED

Like every real light meter, the LM-3000 requires a diffuser to measure accurately. A diffuser scatters incoming light evenly on the sensor and prevents hotspots. While it may sound complex, the solution is surprisingly easy. You have two options:

1) Easily build a diffuser yourself in less than a minute using standard printer paper. This is accurate enough for most use cases.

2) Get the dedicated Diffuser Accessory (free worldwide shipping) for best accuracy and convenience. More details on https://lightray.io/diffuser/

(!) Avoid apps that don’t require a diffuser! They are inaccurate because they ignore the basic physics of light measurement.

TRY BEFORE YOU BUY

The LM-3000 is free to download and comes with a free trial period. The trial period lasts for two non-consecutive days, giving you enough time to see if the app fits your needs. The status of your free trial will be shown as the "battery level" on the top right of the LM-3000's display and on the "Battery Status" screen.

Once your light meter's "battery" is depleted, you may choose a Charging Option to keep using the app. You can pick what works best for you:
→ Single Charge — top-up for another 48 hours (perfect for occasional use),
→ Continuous Charging — a monthly subscription (great if you use it regularly),
→ Unlimited Battery — a one-time purchase for unlimited lifetime access

LM-3000 is the result of over five years of dedicated research and development, ensuring you get a tool that is precise and reliable. Every in-app purchase supports future development and helps keep the app ad-free for everyone.
As a member of 1% for the Planet, we donate at least one percent of all revenue to environmental non-profits — this is our way of giving back.

ACCURACY

Accuracy is not an afterthought — Apps developed by Lightray Innovation are developed according to the ISO/CIE 19476 standard. Thanks to RAW image processing and a default calibration per device model they’re able to match the performance of high quality traditional hardware light meters. To ensure quality we rigorously test our apps regularly on upcoming devices.

DOWNLOAD FOR FREE. TRUSTED BY MILLIONS.

LM-3000 is the go-to light meter for photographers, professionals, engineers, and lighting enthusiasts who rely on accurate measurements — not estimates or guesswork. Download for free today and experience the difference!


See the app in action: https://youtu.be/EJW7NfE2qCk


Terms and Conditions: https://lightray.io/lightmeter/terms/

## Key features

- 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

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Continuous Charging | $3.49 | per month |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Single Charge | $0.99 | one-time |
| Unlimited Battery | $19.99 | one-time |


## What do users think of Light Meter LM?

Overall sentiment: neutral

**Pros**

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

**Cons**

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

**Commonly reported bugs**

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

**Most requested features**

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

## Recent user reviews (10 of 200)

All indexed reviews: https://appshunter.io/ios/app/light-meter-lm-3000/id1554264761/reviews.md

### 1/5 — Ерунда полная

*2026-07-29*

Из за рекламы которая маячит сразу при включении и не уходит,требуя платной подписки,пользоваться не стала.

**Developer response:** Здравствуйте, MonicBell!

Жаль, что первое впечатление оказалось таким — но один момент важно прояснить: рекламы в LM-3000 нет вообще. Экран, который Вы видели, это «заряд батареи» приложения, то есть варианты оплаты. И подписка — лишь один из них: есть разовая покупка на два дня (≈$0,99) и разовая покупка навсегда (≈$19,99).

При установке приложение даёт бесплатную «стартовую батарею» минимум на два активных дня измерений, так что сразу после установки измерять можно бесплатно. Если экран не закрывается и не даёт работать — так быть не должно. Напишите нам на support@lightray.io с моделью iPhone и версией iOS, мы разберёмся.

Как устроена «батарея», подробно здесь: lightray.io/lightmeter/#purchases-explained

С уважением,
Dennis и команда Lightray

### 2/5 — Nah this a’int it

*2026-06-27, version 4.4.2*

Just make a light ad based version for hobbyists and occasional use; the battery stuff is actually just annoying and stupid and not as clever as they would like you to think and needlessly complex. Keep the pro full version as is.

### 3/5 — Good app but

*2026-06-05, version 4.4.2*

Meter worked well but forced me to purchase time to continue use.

### 5/5 — The best ever light meter only available in this platform

*2026-04-07*

Absolutely correct accuracy and 100% authentic readings and most importantly available in free this is an awesome app the first time im reviewing a good application in app store hats off developers

**Developer response:** Hi Rohit54,

Thank you so much for your review and the very kind words 😍 It makes us really happy to hear that you appreciate the hard work we've put into the app 🙏 The highest possible accuracy is our main goal, and it's great to hear that our efforts are valued 🫶

All the best,
Angela and the Lightray team

### 1/5 — 23 EUR für 1 Funktion

*2026-03-27*

Feine super App, die eine einzige Aufgabe hatte und diese super erfüllt hat. Jetzt auf einmal, obwohl sie im App Store als kostenfrei und ohne in-App-Käufe und ohne Abo Modell gelistet ist. Entweder ein Abo oder ein Einmalpreis von 23 € ist schon echt sehr sportlich und spiegelt leider nicht den Wert der relevanten Funktion wider, die sich auch nie ändern wird.

**Developer response:** Hallo Kasatschok,

Es freut mich sehr zu hören, dass dir unsere App und ihre Funktionen gefallen! Vielen Dank für dein Feedback 🙏 Es stimmt aber nicht, dass sie im App Store als kostenfrei aufgeführt ist. In unserer App-Beschreibung sind die gratis Testperiode von 2 Tagen und die Kaufoptionen beschrieben. Ausserdem markiert Apple automatisch alle Apps, die in-app Käufe beinhalten. Du findest den Preis von 23 Euro zu teuer für das, was du kriegst. Das Preisempfinden ist natürlich subjektiv, unserer Meinung nach ist das Preis-Leistungs-Verhältnis unübertreffbar: Du kriegst ein genaues Lichtmessgerät mit vielen praktischen Funktionen und regelmässigen Updates und Erweiterungen, für deine Hosentasche. Oder sogar günstiger, wenn du dich für eine kürzere Verwendung entscheidest. Aber wie gesagt, da gehen die Meinungen auseinander, und das ist okay.

Liebe Grüsse und alles Gute,
Angela und das Lightray Team

### 2/5 — Tired of subscriptions

*2026-03-26, version 4.4.1*

Works well enough before your virtual light meter “runs out of battery” and you have to pay to recharge it or it won’t work. This shouldn’t be a subscription.

### 2/5 — Trial only

*2026-03-23, version 4.4.1*

They don’t tell you this is only a short trial. Two stars for the obfuscation.

### 1/5 — Не понятно

*2026-03-10*

В чем смысл такой платы за приложение, если прибор люксометр можно купить за 1000-1500 руб. вы там куку?

**Developer response:** Здравствуйте Milabone,

Спасибо за ваш отзыв. Ценообразование – сложный вопрос, и мы понимаем, что не можем угодить всем. Мы считаем, что нашли справедливое решение. Все приложение можно протестировать бесплатно, и если оно вам понравится, вы сможете выбрать подходящий вариант из нескольких предложенных. Вы получите точный светомер со множеством практичных функций и регулярными обновлениями — и все это за небольшую цену! По нашему опыту, недорогие светомеры, о которых вы говорите, очень неточные. Но если вы нашли такой, который соответствует вашим требованиям, я, конечно, рада за вас☺️

С уважением,
Анжела и команда Lightray

### 1/5 — Data

*2026-03-02, version 4.4.1*

Bro this don’t work it’s sometimes work and sometimes doesn’t I’m doing a project and this app is not helping me achieve all the data I want

### 1/5 — 49 hour battery runs on a timer?

*2026-03-01*

Hello I needed to have a mic meter for a job I was working on. I downloaded your app and thought that 48 hours of battery power would be plenty to use. Now having this mindset I went to open my light meter for the first time and use it this week after I purchased the 48hr 2 days before. To my surprise my battery was empty and I was not able to use the meter I had paid for. This really is not how an actual physical battery works. I feel taken for and a fool for spending any money on this to not be able to use. I apologize if this was clearly stated in the purchase agreement. But ethically this is not good. Thanks but no thanks?

**Developer response:** Hello Spider-Jon,

Thank you for your feedback and detailed description of your concern. I'm sorry there was a misunderstanding. In our opinion, it is clear that the Single Charge charges the battery for 48 hours from the time of purchase, not only for the hours of actual app use. We also state this in our FAQs (https://lightray.io/lightmeter/#faq). However, of course, we can't expect all of our users to scroll through them in advance, and I can understand how the confusion happened. We will discuss this within the team and, if applicable, adjust our wording to make it clearer. In any case, it is not our goal to mislead our users, and we sincerely apologize. Please contact support@lightray.io so that we can find a solution.

Best regards,
Angela and the Lightay Team

## Frequently asked questions about Light Meter LM

### What does the Light Meter LM-3000 app do?

This app turns your smartphone into a professional-grade light meter. It measures illuminance in lux or foot-candles and correlated color temperature in Kelvin with scientifically validated accuracy, adhering to ISO/CIE 19476 standards.

### What are the key features of the LM-3000 app?

Key features include industry-leading accuracy matching professional lux meters, pre-calibration for your specific device, excellent low light sensitivity, the ability to save peak readings, a HOLD function with an acoustic signal, and a custom calibration option to align readings with another meter.

### How much does the Light Meter LM-3000 app cost?

The app is free to download and offers a free trial period for two non-consecutive days. After the trial, you can choose from various charging options: a single charge for 48 hours, a monthly subscription for continuous use, or a one-time purchase for unlimited lifetime access.

### What are the compatibility requirements for the LM-3000 app?

The app is designed for iPhones and leverages the front-facing camera sensor. It does not require Bluetooth or location permissions. A diffuser is required for accurate measurements, which can be easily made or purchased.

### What are common use cases for the Light Meter LM-3000 app?

Common use cases include professional photography for setting correct exposure and color balance, engineering for lighting design and analysis, and by lighting professionals for ensuring accurate illumination levels in various environments. It's also useful for detecting light pollution.

## Version history (last 5 releases)

### 4.4.5 — 2026-08-25

This update makes the LM-3000 more resilient when working with the iOS camera.

### 4.4.4 — 2026-07-24

This update improves the LM-3000’s performance and stability.

### 4.4.3 — 2026-06-30

This update enhances the usability by:
- Improving measurement rounding
- Fixing the HOLD button's touch area and its interaction with the diffuser warning
- Fixing a bug where the camera kept running while the measurement was not visible

### 4.4.2 — 2026-04-02

Added support for iPhone 17e and the latest iPad Pro M5 and iPad Air M4.

### 4.4.1 — 2026-02-08

This update adds support for Japanese, expanding availability to more users. It also resolves an issue that caused the accessory crosshair placement to appear misaligned on the iPhone 12 mini.

## Apps similar to Light Meter LM

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Light Meter: Lux-525 Pro](https://appshunter.io/ios/app/light-meter-lux-525-pro/id1636117065) | 4.5 (113) | Free | Utilities |
| [Photone - Grow Light Meter](https://appshunter.io/ios/app/photone-grow-light-meter/id1450079523) | 4.6 (4,889) | Free | Utilities |
| [Lux Light Meter Pro](https://appshunter.io/ios/app/lux-light-meter-pro/id1292598866) | 3.9 (5,115) | Free | Utilities |
| [Plant Light Meter](https://appshunter.io/ios/app/plant-light-meter/id1213431133) | 4.6 (1,077) | $2.99 | Utilities |
| [Photo Light & Exposure Meter](https://appshunter.io/ios/app/photo-light-and-exposure-meter/id1297903210) | 4.5 (3,242) | Free | Utilities |
| [Lux Light Meter for Mobile](https://appshunter.io/ios/app/lux-light-meter-for-mobile/id1638732220) | 4.5 (229) | Free | Utilities |

## More apps by Lightray Innovation GmbH

- [Photone - Grow Light Meter](https://appshunter.io/ios/app/photone-grow-light-meter/id1450079523)

All apps by Lightray Innovation GmbH: https://appshunter.io/developer/1031383431

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-27.*