One of my favorite action camera companies that offers many affordable GoPro alternatives is SJ. They introduced me to their first el cheapo action camera, the wonderful SJ4000, which I've used in many videos since then. I've also enjoyed using their SJ Cam M20+, which offers good video stabilization, on a recent trip to Alaska. Now, SJ is back with yet another affordable action camera, this time offering a few more premier features, the S6 Legend.
The S6 Legend offers a few unique features: Mild or Heavy video stabilization, 4K video recording at 25 fps (sharp, but it's interpolated), touch screen controls, and a full-fledged camera app for smartphones (something GitUp is still lacking). Here's the run down on the S6 Legend specifications straight from SJCam: