I have Chromecast device. Thought my Android phone was all i needed to get it to work. Do I need WiFi service independent of my phone's hotspot or Bluetooth , from some other source?, If not what is the WiFi name that both need to be set up on? Can Chromecast work on my TV with just the Chromecast device, my Android which has data service and mobile hotspot and my smart TV? Please help, old school guy very confused and sad because can't get cast to work.