All iPhone and iPad cameras have fairly wide angle lenses. This means that you must stand pretty close to the participants to fill out the image when recording a Photo or Video Finish. Sometimes this is an advantage (e.g. indoors), but in most cases it is the oposite. In many water sports like rowing and kayaking it can be difficult to get close to the finish line. And if the participants have different lanes, like in a 100 m sprint, standing close makes it impossible to set a slice width that fits all runners. This because the runners moves with very different speed as seen by the camera.