Is WP8.1 Fully Functional Without A Sim Card? (Except For Calling, Obviously)

It occurred to me the Lumia 1520 could be the perfect traveling tablet/device (as in vacation touring to remote parts like Ecuador when you carry only one backpack).

I would use a local sim card when traveling. But on my return home, the 1520 is just to big to be my phone.

So the question is do things like location services and navigation work with no sim card? What else will not work?