Light Detector

Last modified
Wednesday, October 4, 2017

Description of App

Have you ever listened to light? With Light Detector, now you can!

Light Detector transforms any natural or artificial light source it encounters into sound. Light Detector is easy to use! Just run the application and point your iPhone camera in any direction. You will hear a higher or lower sound depending on the intensity of the light.

If you are blind, Light Detector helps you to be more independent in many daily activities. At home, point your iPhone towards the ceiling to understand where the light fixtures are and whether they are switched on. In a room, move the device along the wall to check if there is a window and where it is.

You can find out whether the shades are drawn by moving the device up and down.

Bring Light Detector with you to discover what is around you at the speed of light.



Free or Paid


Apple Watch Support

Not Known

Device(s) App Was Tested On


Accessibility Comments

This app is very accessible. There are no controls. Just a 400 hurtz sine wave that varies in pitch when light is encountered. Press home to get out.

VoiceOver Performance

VoiceOver reads all page elements.

Button Labeling

All buttons are clearly labeled.


The app is fully accessible with VoiceOver and is easy to navigate and use.

Other Comments

Simple app that does what it says. It uses the camera on the back of the phone, so hold accordingly. I just loaded this and walked around my home looking for lights. It found them. It found the under water light in my hot tub. I was able to differentiate between them. This is a good general light probe, definitely worth the 99 cents. It's designed to meet our needs, and works exactly as advertised. Not bad for a first version. Now let's see what they come up with next. However, i hold a paid app to a little higher standard than I would a free one. My only complaint is that a sensitivity slider would be nice. I found a small light on my coffee maker, but no way to tell exactly which light was lit even when I covered it with my finger. Having the tone change for a flashing light might also be a nice touch.


11 people have recommended this app

Most recently recommended by Esther 1 year 9 months ago



Submitted by AnonyMouse on Monday, July 30, 2012

Member of the AppleVis Editorial Team
Some very nice update to the already useful app! What's New in Version 1.1 - LightDetector is now more accurate while measuring light intensity. - Tap on the screen to hear (if VoiceOver is enabled) the current luminosity value (from 0 to 100%). The result can be provided with a short delay (within three seconds). - If you tap and hold, LightDetector stops playing.

Submitted by AnonyMouse on Saturday, October 4, 2014

Member of the AppleVis Editorial Team

Just a heads up for the iPhone 6 and iPhone 6+ users. The current Light Detector will not work under these devices. Although, those on the older devices will have no problem when running this under the iOS 8. It appears that there seem to be some problems with the camera that is on the newer phones working with the app. So we will certainly need of an update before this will work. So beware!

Submitted by Nina on Sunday, September 20, 2015

Just a warning to those who use the app. Under this iOS version, light detector doesn't work.
When I opened the app today, I got an alert and VO said,
"We are aware that Light Detector is not working properly On iOS9. We will soon release an update to fix this bug."
And as stated, light detector is not working as it should. The sound doesn't change pitch when the lighting intensity changes like it used to.

Submitted by Nina on Wednesday, October 21, 2015

- iOS 9 compatibility issue fixed