Insta BoothHouse is a free photo booth emulator for your iPhone that looks and feels a lot like the real thing, with bright, colorful graphics, a slick polish to the interface, and a well-made countdown mechanism to help you take better photos. While editing options are relatively limited, the rest of the app works very well, giving an experience you'll enjoy using over and over again.
When you first open Insta PhotoBooth, you can start taking photos right away. The "booth" makes the viewing window for your images fairly small, an issue if you're taking standard facing images but not if you're snapping selfies. You can open images, as well, including old strips you've already taken in the app. The "power" button is how to get started. It will count down from three, four separate times, snapping a photo with each countdown and creating a photo strip. You can choose how your strips will look but you can't do much else; the editing tools are pretty limited here, which is a bit of a shame.
If you want to create candid photo strips, this is a great free app. There are filters and a few other editing tools to customize your images, and while you can't make major changes to individual images, you can prep them for sharing in a lot of ways. The app is free and ads can be intrusive, at times, but they manage to stay just far enough back to keep from interrupting the experience. This is a generally very good app.