CamWow is a simple Windows Phone 8 photography app that allows you to apply unique filters to your photographs. CamWow won't let you apply the creative effects to existing images but if you're looking to put a twist on new images, it might be worth a try.
CamWow's user interface is about as simple as it gets. You have preview windows for each filter and three control buttons at the bottom of the screen. Just swipe left or right to choose your effect, tap on the preview window to pull up that effect, line up your shot and tap the screen to capture the image.