We've always loved PicMonkey online, it's our go to tool when not able to use Photoshop. When they released their app we jumped on it, like a monkey. Monkey. LOL.
There's also a cool thing called their "hub" where you can save your images in their cloud. Which is brilliant if you don't want to clutter up your phone storage. To use the hub you have to have a ROYAL account which is about $4.95 per month, but also allows you to use all the features of their editing program (which you only use online so you don't have to download or install any pesky software/programs).
Here's a few ideas of what you can do.
Would love to see your edited photos or images...leave a link in the messages to your pics.