Phone use on Apple watch
Can I make and receive phone calls on my Apple watch without cellular as long as my iPhone is on my body?
Apple Watch
The GPS only Apple Watch (or a cellular model without a contract) can do Everything the cellular model with contract can do as long as your iPhone is nearby. Where nearby is say in the same house assuming a 3-4 bedroom 2 story house using wood frame construction.
Read this, especially the footnotes
