Photo Sketch comes with a huge number of cool filters, but the obnoxious ads don't do it any favors. If you can stomach those, it's a very cool app that has style that you won't get in many other places.
This app turns any photograph on your phone or tablet into a sketch. All of the app's filters revolve around making your photo look like it was done with pencil, markers, or other drawing equipment. There are dozens of filters and borders for you to choose from, and most of them look really beautiful. You have the option to log in with Facebook, but you can still share to other social networks from the app if you don't. The app is very responsive to your touches, but it doesn't have its own built-in camera. You'll need another camera app to shoot photos for the app to filter. In addition to being covered in ads, Photo Sketch tries to make you agree to a nasty ad agreement that will put ads all over your browser and home page. Sadly, that seems to be the norm for free photo editors.
To its credit, Photo Sketch doesn't just completely steal Instagram's style to hit you with ads. Instead, it presents a unique way to edit your photos. If you're not bothered by the ads, this is a worthwhile download.