There are a lot of photo editing apps available for iPhone and Android. I’m going to list my favorites. To find any of them, just go to the app store and search for the name.
Instagram – Free for both iPhone and Android
You can’t beat this popular social photo sharing app for simple cropping and filters. It’s also a fun way to share photos. You are limited somewhat by the shapes of the images you can post. It’s very easy to navigate.
Snapseed – Free for both Android and iPhone
This astonishing app offers you the kind of editing options you’d expect from an expensive desktop program like Photoshop.
There’s a bit of a learning curve, but the results are amazing. It’s very touch-friendly.
BeFunky Photo Editor & Collage Maker
Free for iPhone and Android – Optional In-app purchases.
Plenty of filters, stickers, and other fun add-ons make BeFunky a ton of fun to play with. It has more options than Instagram and is much simpler to use than Snapseed, but it still gives you a lot of great editing options.