DJI is taking on GoPro with their new camera, Osmo Action. In addition to the usual rear screen, it has a screen on the front -- making it perfect for selfies and vlogging. It also shoots in 4K in HDR at 60fps, and can do up to 240fps slow-motion. We put it to the test -- whether by shooting time-lapses of Hong Kong's skyline or by diving in Taiwan, check out our review for more!