With the newer iterations, you can. I bought a series 5 used off ebay and plan to try using it independently. It's obviously not going to give you the full func

With the newer iterations, you can. I bought a series 5 used off ebay and plan to try using it independently. It's obviously not going to give you the full functionality of a full-sized phone, but if we're talking minimalist phones I don't think that's the point anyway. Maps + (very) basic texting + phone calls.