Snapseed is a powerful photo editing app for your iPhone or iPad. While iOS has basic photo editing software built into its Photos apps, Snapseed does everything better and has more features.
Between basic and professional
Snapseed strikes a good balance between amateur and professional photo editing. There's your typical level adjustments for exposure, contrast, highlights, etc but there's also a bunch of filters for quick adjustments. Don't like the filters that came with Instagram? Give Snapseed's a try.
All edits are non-destructive, so you don't have to worry about losing the original photo. If you don't like how your edits turned out, you can undo the changes or go back to the original photo.
For more advanced users, there's a spot removal brush to help you remove small blemishes from your photos. It's a nice feature that can help you perfect your photo before sharing on social media.
A made-for-mobile interface
Snapseed was built from the ground up as a mobile product. You'll be swiping left and right to control the strength of your edits. Everything is logically laid out and easy to use. Tools are laid out in a grid and it's easy to understand what each of them does. The interface is extremely minimalistic while you're editing, helping you maximize your view of the photo.
I found the effects and filters in Snapseed to work very well, though some make photos look too dramatic by default. But you can tune the image to your liking. There's a slight learning curve to using the app but most users will be able to pick it up within a few minutes.
One of the best mobile photo editors
Snapseed's ease of use and feature set make it one of the best photo editing apps for mobile. The app is designed for touch and makes adjustments easily. If you want more control over editing your photos on the go, Snapseed should be on your short list of apps to try.
Also check out VSCO Cam for beautiful filters and excellent editing tools.