If you are looking for an outstanding 4k handheld action camera, take a good look at the DJI Osmo Action.
This waterproof stabilized camera has a dual screen that makes it possible for you to see from any angle and stay in-frame. A vivid front screen lets you frame yourself easily in any setting, while the back screen is a hyper-responsive, crystal clear display. The RockSteady Stabilization feature creates amazingly smooth videos even if you are riding on rough terrain. RockSteady combines EIS with complex algorithms so it delivers stable, shake-free footage no matter how complex the action gets.
The Osmo Action is extremely durable as it can operate in temperatures as low as -10 degrees Celsius, and is waterproof to depths of 11 meters. With these kinds of specs, you could surf for several hours a day or go snowboarding and catch amazing footage!
If you want to learn more and buy your own DJI Osmo Action, just click on the link at the top of the page.