Does the BlueLink app use Wifi or just the cell data connection? Sometimes when I have a weak signal it tells me something about reviewing my car's package (usually happens when it can't connect) and other times it fails even though I can log in. My sister has shotty Wifi (it'll show a strong signal but will still take forever to download anything, then at other times it's normal & high-speed) but even when it seems to work I still couldn't get the car to remotely start. I'm not sure if it's her shotty Wifi or a bad signal or both. Does it switch to Wifi if available?