Switching from "In" to "Out" allows the user to start at the full zoomed in and step to the full "Out" zoom range. This is useful if the object you are photographing is coming toward you such as a mountain bike rider coming down a trail toward you.
There are two modes, "Auto" and "Manual". In auto mode, the automatically takes the photos in rapid sequence. In manual mode, a small shutter button appears in the center of the screen. The app waits for you to press the shutter button. Once you press the button, the app captures an image and then waits for the next press of the button to zoom to the next incremental zoom setting and take the next photo.
The bottom of the screen has four buttons which set the number of photos the app will capture. The buttons are labeled "3" "6" "8" and "10". In "Auto" mode, once you press one of the numbered buttons, the app begins to capture and incrementally zoom until the corresponding number of photos have been captured.