The light metering tool for every great image maker.

Use the standalone app as a reflective light meter or use it in combination with Lumu Power hardware for professional Flash and Color Temperature measurements.

Lumu Power is an easy-to-use digital incident color and light meter that works seamlessly with the free Lumu app to deliver Color Temperature, Illuminance, Spot, Ambient, and Flash Exposure metering functionality on your iPhone.
A new expression of what a light meter can be, Lumu meets the needs of enthusiasts, professionals, and students who find existing light metering solutions too bulky, expensive, and complicated.

“The Lumu Power is without any doubt the most full featured light meter I have ever owned. It’s tiny, it weighs hardly anything, it manages to offer a feature set that expands way beyond what most will ever need from such a device.” -

Key features:

- SPOT METERING: Use your phone’s camera as a reflective light meter.

With Lumu Power:

- PHOTO SINGLE mode: Giving you exact parameters: exposure time, f-number, ISO, EV, lux.
- PHOTO MULTI mode: Calculating average value or contrast between multiple measurements.
- PHOTO PINHOLE mode: Measuring exposure time for custom pinhole camera settings.
- CINE/VIDEO mode: Set FPS, F-number, exposure time and ISO. Get the values for the ambiental light.
- FLASH EXPOSURE: See the graph of flash duration, measure its intensity.
- COLOR TEMPERATURE: Read light Color temperature in Kelvin and Green/Magenta shift.
- CHROMATICITY: See light colour in CIE1931 diagram and get X,Y,Z coordinates.
- ILLUMINANCE mode: showing incident light level in lux / foot-candle values.
- NOTES: Store all your measurements together with geo-location, custom notes and your photo in one place.


Visit to learn more.

What’s New

Version 3.3.2

Hey Lumunauts,
Thanks for using Lumu Light Meter!
Here's what's new:
- minor bugfixes
- Japanese, Norwegian, Swedish, German, French and Arabic translations

We hope you enjoy this update, and if you run into any troubles or have a suggestion for the app, let us know at

Ratings and Reviews

4.0 out of 5
42 Ratings

42 Ratings

Heath Shelton ,

Not as good as I thought

Just received my lumu power and it does not read flash as good as my 21 yr old sekonic. I have to be right next to the flash before it will read. I can not stand where I put my subject and read the flash like I do with my sekonic. I was excited to get because I would not have to carry an extra device around but I’m gonna still have to.

Jamdalu ,

Does the Luma “Pro” Dome require In-App purchases?

The app is really nice! I am ready to purchase a dome and would like to know if the Luma Pro dome requires additional in-app purchases to “unlock” the pro features. Are the in app purchases merely upgrade options for the lower priced units? The pro model seems to have everything unlocked at $499 when combined with the free app, since it’s the only one without this flag: * If necessary, additional modes can be unlocked directly from the app after purchasing this model. Do all three domes share the same hardware, upgraded by the app? I want all of the pro features, and would like to know the final cost to unlock all features. Thanks!

a random player named jon ,

Try this app first!

Just what I was looking for! I have been looking for a luminance / light measuring app for an experiment I am doing for a long time. I have been through a number of apps before this one, which finally met the need! Other apps hit you with frequent ads, or don’t let you make camera adjustments, or don’t show results in real time. This app is either ad free, or low frequency of ads, lets you make camera adjustments, and shows results in real time! It allows for a number of adjustments, is easy enough, and seems to be fairly precise in detecting fluctuations (which I am looking for). A big thank you to the creator(s) of this app!


Lumulabs d.o.o.
72.9 MB
Photo & Video

Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.


English, Arabic, French, German, Japanese, Norwegian Bokmål, Swedish

Age Rating
Rated 4+
© 2018 Lumulabs
In-App Purchases
  1. Power Upgrade $159.99
  2. Pro Upgrade $119.99
  3. Pro Upgrade $299.99


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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