Fotor Photo Editor is one of the best free photo editing tools on the App Store for a number of reasons, not the least of which is the slick design that has been polished over the years. Loaded with color, lighting, and graphic effects that allow you to customize your image to no end, Fotor Photo Editor is built from the ground up to be as close to a full-featured image editor as you're likely to find for your iPhone.
After opening Fotor Photo Editor for the first time, you can choose from a number of options. Load an image from your Photo Library or take a new one from your Camera, and then start selecting any of the number of filters available in the app -- including scenes that change all of the features of the image, saturation editors, contrast, and FX effects. You can also add borders to the image, text effects, tilt and shift coordinates, and more. It would be easier to list what this app cannot do, but you'll find all the basics and more. The interface is designed for ease of use, as well, with twin sliding menus at the base of the screen, collage creation tools in a separate menu, and a photo box tool that makes it easy to save and share images with the desktop app.
If you are looking for a feature-rich photo editor for your iOS device, Fotor Photo Editor is one to check out. Loaded with features, easy to use, and polished to a sheen, this is a truly great app.