I've made this app for real old school photographers or advanced amateurs shooting analog photography. For the price of a soda you will support hundreds of hours of work. LightMeter's reflected light meter only works with devices that are able to save exposure to exif. Incident light meter usually works on any device but... Be advised that the precission and quality of this and all phone light meters is limited by the device itself. I recommend using the reflected light option, the precission can be really good. Features: -ISO range from 3 to 6400. -Incident light metering (needs light sensor) -Reflected light metering (needs camera, only a few are compatible) -Low light alert. -Camera can be muted. (not in all countries) -Exif and sensor info displayed on screen as an option. -Calibration. -Vibration on measure/hold. -Incident light reading can be held. -Alternative ISO selector. -State and ISO recall on resume. -Spot measure if camera has zoom. -Support for all screens, including extra high resolution. Thanks for your support If you need help email me at [email protected] (Spanish and English)