(Stay or go? A fundamental precept...
All some people want from a GPS is the ability to get back to the rig. They may be knowledgeable about wilderness survival and carry a survival kit, but they aren’t into geocaching, aren’t particularly concerned about where they are at all times and don’t care how many waypoints the receiver will store.
Trash bags are included in all my survival kits. They have a multitude of uses, including being containers for picking up trash! But in an emergency, when correctly used, trash bags can prove a quick, temporary shelter from the elements.
TV survival shows to the contrary, it is virtually impossible to make a waterproof shelter out of natural materials, even if you have the time, tools and practice! Even with a tarp, you must have some idea or plan on how to fashion a refuge from the elements