Here's how you can take photos while you are recording a video in iOS 6 on your iPhone 5 or 4S.
1. Open the camera app.
2. Move the slider from in the bottom right from photo to video.
3. Begin recording your video.
4. While your video is recording, tap the camera icon in the upper right to take a photo.
5. You'll see the shutter close on your screen each time you snap a photo.
6. Your photos will be saved to your camera roll.
You can take as many photos as you want while recording your video.