i guess i'm late to the party

A couple days ago, I was checking to see what new videos were up in my YouTube subscriptions. I came across a video done by Glamourista16 that was all about how she edits her Instagram photos. Instantly I fell in love and looked up basically all the apps she mentioned in her video. I'm pretty sure I'm late to the party on this one, and I'm assuming all of these apps have been around forever. But they're new to me and so much fun! The three I've been messing around with the most are A Beautiful Mess ($0.99), Afterlight ($0.99), and Papelook (FREE!). So many fun features-

What are some of your favorite photo editing apps?