Filmic Pro The official APP for Smooth 4 is called ZY play. But Filmic Pro has best in class support for Smooth 4, you can use Filmic Pro as an alternative to ZY play. Control Panel Integrated control panel design,Focus Pull & Zoom Capability MUST KNOW Balance the gimbal before use: Slide the smartphoone in as close as possible to against the tilt axis motor. Loosen the Roll (Y) Axis Thumb Screw (which is on the back) to adjust the gravity center by sliding the horizontal arm.When phone stays in level in power OFF status, it is balanced.We recommend you VIEW the video tutorials, There are lots of tutorial videos on YOUTUBE that will help you master the gimbal