Take your photos and videos to the next level with the Lumu Power Light & Color Meter. This device attaches to iOS devices running iOS 8.0 and up through the Lightning port. It has two sides: the dome side measures ambient and flash exposure up to 750,000 times per second with a range of -4 to 20 EV, and the flat side measures illuminance, color temperature, and chromaticity using a True Color sensor based on the CIE 1931/DIN 5033 color standard. Illuminance can be measured in a range of 0.15-250,000 lux and color temperature from 1500-20,000K. The Chromaticity Mode displays coordinates in the CIE 1931 color space.
It uses a free iOS app to display color and light information on your screen so you can adjust your shots accordingly. The Lumu Power needs no batteries; it runs off your iOS device's power. It's made of stainless steel and Lexan polycarbonate for durability.