It's photo week on the blog, so we're exploring some of the cool paid apps that let you do surprising things with your iPhone's camera. CameraBag (temporarily $2.99, available here) lets you create different looks with your iPhone's camera, such as imitating the output from a plastic Holga camera (here called "Helga") or creating smooth black and whites, a la Ansel Adams.

Other looks include 1974 (faded and tinted), Lolo (over-saturated color, like a Lomo camera), Cinema (dramatic and moody), 1962 (dramatic black and whites), and Infrared (simulates a popular landscape photography technique).

Taking photos with CameraBag is incredibly fun. We love how bizarre the Helga setting makes portraits, or how the Lolo setting makes still lifes pop like a diner's neon sign. The app also works with pictures stored in your photo library, so you can give any image the CameraBag treatment.