A DNG file is a high-quality image format that is quite common even though it's a relative newcomer compared to some file types such as the TIFF format, which is decades older (2004 vs 1986, respectively).
Magic Lantern may soon release their most popular feature since RAW video. A few of the folks who constantly improve the Canon software add-on have just found a way to generate 14-bit lossless DNG RAW files in-camera!
About a year ago, we shared an app called 645 Pro that saves photos shot with the iPhone (and other iOS devices) as TIFF files. Now there's a new app that's even more "raw". Digital Negative, a new app by a company called Cypress Innovations, claims to be the first app that captures uncompressed images that retain 100% of the information captured by the camera sensor.