In reply to NinaC:
The best tripod will depend a lot on where you are.
The gorilla pod is great for perching the phone on almost anything, but obviously you can only take pictures from the angle of the thing you're perched on. If you're at a sea cliff with boulders, slopes, etc. there will always be interesting angles to find, but at a flat bottomed quarry you might find everything getting taken from the one angle - straight up at the wall.
A traditional camera tripod with an adapter for your phone allows getting the camera up to head height off the ground, which can make the angles seem more natural to the viewer.
If you want to shoot video rather than stills, a gimbal that can be programmed to move as you climb can be useful, but they tend to need flat ground to stand on their own. A gimbal with a standard tripod screw can be mounted on a camera tripod, to give you the best of both worlds, but costs a bit more to get both obviously. I have a zhiyun smooth 4 which I love a lot, and can be picked up second hand for not much more than the gorilla pod you linked above.