While you can take decent photos with the camera hardware built into the iPhone/iPod Touch/iPad, it'll never come close to what you can produce with a DSLR. A new iOS app, called Digital Negative, might not be able to do anything about the sensor or lens, but at the very least, it can make sure the images you do capture remain unprocessed and uncompressed.
Priced at $2.99, Digital Negative's app description boasts that it is "the first app that captures uncompressed images that retain all of the information recorded by the camera sensor". It claims images are saved as DNGs -- a raw, lossless format pioneered by Adobe. It also comes with various tools for examining and modifying images, including real-time histograms.
If the functionality sounds similar, you're not going crazy. It's likely you've heard of, or even own, 645 PRO, an iOS app that produces "zero" compression JPEGs and unmodified TIFFs from your snaps. It's not entirely clear if the DNGs that Digital Negative creates are just wrapped-up JPEGs, or created by talking directly to the camera.
I plan on giving it a try, but if you've already taken the plunge, let us know what your experiences have been in the comments -- especially if you also have 645 PRO installed.