How do I track my cat?

Just got my first Pawscout and I love the concept!  I can see when my wayward cat is within 300' of our home because the circle turns green.

Do buildings get in the way of the bluetooth connection?

What if I want to walk around and find him?  If I click 'enable leash' it says he has to be in range to enable it. I want to be able to walk down the street and have the green circle light up when he is in range of my phone, not necessarily when my phone is in my house.

thanks!