What's the role of using handheld pan/tilt in mobile photography?

If you don't use a hand-held pan/tilt, the video will be very shaky and you can't watch it. Hand-held pan-tilt mainly plays the role of automatic leveling and stabilizer. With it, as long as you don't tremble and bump up and down (this can't be stable), you can overcome the left and right shaking and the back and forth shaking, and the video you shot is relatively stable.