Their tagline is “Bring DSLR-like Photography to Your Smartphone.” And it’s very true. You have lots of focusing, color changing effects, and more. AfterFocus does a surprisingly good job considering it’s “not much more than a mobile app” – oh, and considering that it is free on the Google Play Store! Below is one of their sample pictures where they show changing the backdrop of a photo to black and white, while leaving the rest alone.