Most GoPro cameras can film in 4K (3840 x 2160), but older models are limited to standard HD (1920 x 1080). Premium models can film in 4K at higher frame rates like 60 frames per second (fps), which results in smoother, more realistic video. If you need superior 4K video quality, you’ll need to look at the more expensive GoPro cameras, but if you need great but not amazing video, you can save a decent amount of money by getting a prior-generation model that records in HD.
And sure, those options could include your waterproof and crack-resistant smartphone, but keep in mind that the best action camera is designed for this kind of shooting. Plus, just because your phone is tougher, it doesn't mean you should risk losing or damaging the thing that keeps you connected to work, family and friends. It's also way easier to mount one of these to your body, car, bike or anything else than your phone.
You get many of the same shooting modes you'd find on a GoPro device, such as time-lapse photos and videos and slow motion footage at 1080p at 240 fps, and there's even a Drive mode so you can use it as a dash cam when plugged into your car, automatically turning on when you start your car and off when you stop it. It's not waterproof on its own, but a dive housing is included as well as several mounts, two batteries and a charger that simultaneously powers up both packs. It also has built-in Wi-Fi so you can connect to a smartphone and use an app to control the camera and transfer your shots for sharing.