GoPro may have popularized the action camera market, but there are plenty of competitors these days. YI came on the scene as a producer of affordable alternatives early on, but its latest release, the Discovery 4K, takes inexpensive action cams to a whole new level. The Discovery 4K has been discounted to just $47.99 with a coupon code applied at checkout.
Of course, while the Discovery 4K is a good deal for the money, it's not as fully-featured as its upmarket stablemates. It can shoot 4K, but only at 20fps; it also shoots 1080p60, which is probably what you'll be sticking with. Its 8MP Sony IMX179 is the same sensor used on the Nexus 5, though it does have a 150-degree wide-angle lens. It has a 2.0" LCD touchscreen, which is pretty surprising to see at this price point. Eight shooting modes are present, and built-in 2.4GHz Wi-Fi allows it to connect to your phone within a 100ft range. It's not water-resistant, though IP68 water resistance can be added with a case that is sold separately.
To get to that $47.99 price, you'll need to enter code FBYFC3CQ at checkout. Shipping is free, as it usually is on Amazon. If you've been in search of a cheap action camera, this is definitely worth consideration.