Luxi is a small diffusion dome that fits securely over your iPhone’s front-facing camera allowing it to be used as an incident light meter on those occasions when you want to take perfectly exposed photos with your more serious camera(s). Although light meter apps featuring an incident mode are readily available on iTunes, the fact that the iPhone wasn’t designed to function as a hand-held exposure meter means there are hardware limitations to their usability. “Luxi is designed to work just like a professional incident light meter which can capture light from a 180° angle,” the inventor says. Funded through Kickstarter, Luxi has already exceeded its $10,000 goal by a very wide margin. The ingenious adapter will retail for $24.95 but you can still get one for as little as $19 by backing the project. The product comes in two versions, one for the Apple iPhone 4/4S and one for the iPhone 5.