To capture photos without a proper source of light, you'll need to slow down the shutter speed to expose the sensor to more light. Pretty much any manual camera app will let you adjust this setting, but Slow Shutter breaks it down in such a way that it's easy to understand and control. When shooting in the dark, real-time sliders for exposure boost and shutter speed will let you adjust the sensitivity to capture the desired result. It's meant to simplify the process for amateurs, but pros will appreciate its no-fuss approach.
And it's not just great in low-light situations. Shots that look best with long exposure--such as running rivers or zipping cars--will benefit from the motion blur and light trail modes that offer the same easy adjustment sliders, ensuring you don't mess up a great shot fumbling with confusing controls.
Best for editing: Rookie Cam
If you want to do more than touch up your photos or magically remove red eye, you'll find everything you're looking for inside Rookie Cam (free).
As a camera, Rookie is fairly rudimentary, but snapping photos is only a small part of what it does. Where the other cameras in this list are mostly built to help you take the perfect shot, Rookie goes to work after the moment has been captured. Along with a standard set of editing tools, the app offers a heap of design tools to dress up your pics, from filters to badges, fonts and frames, all with the explicit purpose of transforming your snapshots into slick works of art. The app comes bundled with a nice selection of features, but a few bucks will unlock a trove of customizable goodies that will make the dullest of photos suitable for sharing.
Some of Rookie's options are admittedly amateurish, but that's part of its appeal: Simply scrolling through the scores of stickers and shapes can put your photos in a new light and open avenues of creativity you wouldn't otherwise discover.
Others of note
Paring this list down to six camera apps left many great ones on the cutting room floor. That includes my personal favorite: ProCam 2 ($5). ProCam used to be my go-to app for taking photos: Its shooting modes let me snap quickly, while its manual settings offer tremendous control. It takes some time to learn--even beyond what it takes to decipher VSCO's minimal interface--but there isn't much it can't do. Its interface isn't quite as intuitive as the others here, but you can learn a lot about digital photography by exploring its settings. If I had to create a category for it, it would be "Best for novice photographers who are ready to start using a more advanced camera."
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