Lock in an accurate exposure with the exceptionally portable Lumu Light Meter, a simple module that connects directly to your iOS device via the 3.5mm headphone jack. This incident meter is compatible with iOS 7.0 and later and utilizes a digital silicone photodiode along with a hemispherical cardioid-type diffuser and black aluminum body to measure ambient light. It offers a wide measuring range of 0.15-250,000 lux, or EV -4 to 20 at ISO 100, and has a rated repeat accuracy of 0.1 EV. Additionally, it does all this with minimal power draw from your device. 

In order to optimize usage for your applications, there are three iOS apps available: Photo, Video, and Pinhole. The Photo app is designed for stills shooters offering a variety of controls, metering options, and settings, including a reflected light mode using the device's camera. Video users will be pleased by their own dedicated app which adds much needed motion parameters such as frame rate to the mix. And, the Pinhole app allows extreme long exposure photographers to work alongside a timer and accurate metering system. 

This meter is very convenient coming in at just 0.94 x 0.78" in size and it has 0.09" of free space between it and the device in order to remain bumper-proof. Also, it comes with a leather neck strap and storage pouch to ensure your investment is either by your side or safely put away.