Now that iPhone can record 3D video (https://www.tridimensional.info/apps/espanol-smartphone/) you can make a custom tripod to hold two iphones this way:
You can borrow or rent another iphone.
This also allows to record 3D videos with variable stereo base, so landscapes will be 10x times more impressive than 4V.
Already looking for more people publishing their 3D creations on YouTube