CameraPlus.
Agree with Willo, quickly becoming my favorite photo app. I personally love the quadrants to help guide your picture area and ton of features that help improve lighting and colors. Lots of fun special effects, cropping, and a stabilizer.
Diptic
Great for creating fun collages of pics!
Download
Big Words
For ordering drinks at a loud bar and other fun random uses. Willo has also cleverly used Big Words to type her contact info and made it her Lock Screen (via screen capture). Read, people know who contact if they find her phone. (And I have been with her on one such occasion.) Brilliant!
Boxcar
Boxcar sends you push notifications, alerting you to mentions on Twitter and Facebook. Especially useful at events.
Evernote – capture notes and sync across all devices. Stay organized.
I’m becoming more and more of a fan! Great and free way to capture, organize, and track notes, websites, pictures, etc.
