Meet the GENEINNO Titan: a smart underwater robot that can go down to a depth of 150 meters and record 4K UHD camera. It also features 1080p livestreaming capability. You can use it with a pair of goggles to get an immersive view of all the action. The robot uses 6 thrusters to achieve max speed of 2 m/s.
Titan not only has a 4K UHD camera but also 3000-lumen lighting. It connects to a WiFi enabled buoy, which in turn connects to your smartphone. More info is available here.