The Phoenix Photo Editor joins a crowded field of photo editors for iOS, but it's free and has a wide selection of features.
Of course the app has the usual filters and tools for cropping and saturation. It also adds high-end features like lighting effects, vignettes, selective blur and a nice variety of frames.
One sign of a good app is not needing help when first exploring it, and the Phoenix Photo Editor lets you get right to work without needing pages and pages of explanations. Many photo editors skimp on undo features, and this app lets you go all the way back to where you started, a step at a time.
Metadata is preserved when images are edited, but you can elect to add or edit geolocation information, which is nice. Images do not save in full resolution. On the iPhone 5s, which has a resolution of 3,264 x 2,448, images save at 3,000 x 3,000. Anything with a higher resolution will save at that size.
Although the app is free, there are 10 in-app purchase packs at US$0.99 each. I didn't find any of them absolutely necessary, but I thought some of the lens flare effects might be worth it for some photographers. I felt I could do a good job of editing any photo from the free version. I especially liked the color splash tool, which lets you selectively add or subtract color from an image. The effect can and has been overdone, but when used artistically, it can really make a photo quite striking.
There are plenty of ways to share photos, including Facebook, Twitter, Instagram, Flickr, Tumblr and Google+. Of course you can save to your camera roll and go anywhere from there.
I'm still partial to Snapseed (free) for photo editing on my iPhone and iPad, but the Phoenix Photo Editor brings quite a few tools Snapseed does not offer. Still, Snapseed has more powerful color- and contrast-enhancing tools.
The combination of the Phoenix Photo Editor and Snapseed would be a powerful one, and might be all the serious iPhone photographer needs, but everyone has their likes and dislikes, and there are hundreds of worthy editors being offered.
The Phoenix Photo Editor is not a universal app, which is a shame, but the developer tells me the iPad version is ready and awaiting Apple approval. The app requires iOS 6 or greater, and it's optimized for the iPhone 5.