I have access to wifi at the college campus and turn it on... but the wifi drops when I move around going to my classes. So I usually just leave it off until I need it. I know that depending on the network and area, wifi is generally faster than a 4G connection. How does this impact battery life on my phone? I'm thinking it would run the battery down less if I left it on 4G and did not keep turning the wifi connection on and off.