I'm getting my rezound in the mail tomorrow (YAY! first smartphone/phone ever for me) and I want to make sure I use as little data as possible at home. What settings or apps should I download for my rezound to assure that when I am at home only WiFi is used? Because I read that when the phone goes to sleep wifi shuts off and 4g takes over. Please help I only have 300mb data to work with per month. Which really should be fine since I have WiFi at school and home, where I am 95% of the time.