Tesla has now created an in-car Dashcam / Sentry viewer that you can use on the car's screen. If you just want to view your Sentry videos, that viewer works and you may not need this app. But the app provides some functionality beyond what the in-car viewer has: -More responsive and reliable than the in-car viewer -Faster and slower playback speeds (.25x to 16x) -Share and Save clips -Zoom in and save full-sized screenshots -Create composite videos that merge multiple cameras into a single video