Editing software has long enabled filmmakers to can create split screen and picture-in-picture effects.

But now, the DoubleTake app by FiLMiC Pro makes it possible to achieve these visual tricks while shooting. The app shows you what is being captured by all of the phone’s cameras. You then get to choose two of them, for example, the telephoto and the wide-angle, or one of the front cameras and the back camera.

Here’s a tutorial from FiLMiC.