Light Meter LM-3000 4+

Simple & accurate measurement‪!‬

Lightray Innovation GmbH

Designed for iPad

    • 4.6 • 894 Ratings
    • Free
    • Offers In-App Purchases



Measure Illuminance in lux or foot-candle with the most accurate light meter app out there.

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

We offer the same quality and usability than a handheld or pocket light meter. You won't need any additional light sensor — the camera already got you covered. Our app is equipped with a clean and simple user interface and most importantly: No Ads!

See it action:

Besides that, our app is even more accurate than almost any cheap light meter available. It is tested and calibrated using professional Class A equipment for all iPhones and iPads — truly a light meter you can trust!

Download the app for free and use it for some time! If you like it, you may buy the unlimited battery pack to use the LM-3000 for as long as you want, even when switching to a new device. Your purchase allows us to provide an Ad free experience and helps our small team to keep on building great apps to measure light accurately and easily.

If you encounter any problems or have feedback, don't hesitate to contact us:

As a proud member of 1% for the Planet we are donating at least one percent of all our revenue to environmental nonprofit organizations. With everything that you purchase from us, YOU will be giving back!

What’s New

Version 1.8.0

We've updated our user manual to contain more information on how to use the LM-3000 app correctly.

Ratings and Reviews

4.6 out of 5
894 Ratings

894 Ratings

steff782 ,

Easy to use and seems reasonably accurate

Tried on daylight (110k) and on 7500 lumen 40 degree led bulbs at 3 ft, got 15k instead of expected 21k, but probably partly because bulbs weren’t perfectly focused? Anyway, accurate enough for me! Just wish it had family sharing enabled, I’m going to get the other light meter app that does have it for the same price.

Developer Response ,

Hi steff782,
Thanks for your detailed feedback! I assume so but to understand your calculations better, it would be great to reach out to our support with the specific type of LED light bulb. The family sharing is a good input and we'll definitely consider it.
Best regards,
Dominik and the Lightray Team

KJPA77 ,

This is a scam

Free? When I first opened it I was required to make a light diffuser. Hmm okay. Easy enough. Once I got that attached to my iPhone the app popped up saying the meter ran out of battery and it would be $7.99 to purchase a lifetime battery. No options. My phone battery is 100% so that’s not the problem. This thing actually costs $7.99 if you want to use it. I wouldn’t be surprised if it continues to demand future purchases of something or other in order to use it. BTW, I have no idea if the light meter works. I never got that far.
Update after developer’s response: I’m not confused about it being my phone battery. I’m confused how Apple lets you act like this is a free app but it’s only free to download, not free to use. It should be sold as an app for $7.99. It might even be worth it. But I’ll never know because I won’t trust a developer that says the app is free when it’s not.
Update again after developer reply that this is a “try before you buy” app. No, it’s not. I didn’t get to try it. First it told me I needed the filter. So I made that. Then when I tried to use it, I got the message that the battery was empty and I needed to pay $7.99 for the lifetime battery. I never saw any light measurement at all. Why would I pay for this? You guys need to try using this from a phone not registered to one of you and see how it really works. Edit: I’m a systems analyst, software tester, support team member so I have some experience in this realm.

Developer Response ,

Hi KJPA77,

Thank you for reaching out with your feedback. 

It seems like the hypothetical battery of our light meter resulted in some confusion: It has nothing to do with your phone's battery. As the intention of our app is to replace a dedicated (and costly!) handheld light meter, you also won't need to purchase anything else in our app and the "battery" is valid a lifetime as long as you use the same Apple ID. Please feel free to reach out to our support if you need help to get it to work.

As you can imagine, developing an app requires a lot of time, effort, and money. To compensate for this there are basically two options: Show you tons of ads and thus also "sell your data" OR offer a paid or freemium app...that's why we've chosen the latter. 

BTW, it works very well. You can find more information about the accuracy on our website.

Best regards,
Dominik and the Lightray Team

Updated response:

Hi KJPA77,
I understand and we could consider making it a paid app right away. However, we've chosen this approach to offer a "try before you buy" option so users can get a sense of our product before having to buy it. More information about this trial can also be found in our app's description.
Best regards,
Dominik and the Lightray Team

Krablips ,

Totally Disappointed!

Greatly inconsistent readings. Every time the diffuser is removed and reapplied, the lumen readings are very different. They are inconsistent to the point of this app being unusable. I “cannot “ rely on the readings accuracy nor precision. I made, applied, and used the diffuser exactly as instructed. I was very exact that I placed the diffuser in the exact same position every time I reapplied it to my iPhone. After the diffuser wasn’t giving repeatable readings, I created a second diffuser and again received unrepeatable readings. Every time the diffuser is taken off and reapplied I received different readings. The difference in readings were sometimes over 100 lumens. We’ll there goes $7.99 down the drain.

Developer Response ,

Hi Krablips,
Thank you for your feedback. This obviously isn't how it should work and most likely stems from your diffuser (paper) being too heterogeneous in its structure. You can easily make this test as you mentioned by re-applying the same diffuser. If you find your diffuser to produce varying results, you could switch to something else such as a more uniform paper or a piece of plastic (e.g. yogurt container piece etc.) and calibrate accordingly. Which yes, is a bit of a hack. You can always reach out to our support and we'll happily help you to resolve the issue.
Best regards,
Dominik and the Lightray Team

App Privacy

The developer, Lightray Innovation GmbH, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

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