Bluetooth or Wifi?

Hi everyone,

This is likely a stupid question but I can't figure out how the infotainment system works. For example, usually I'm connected by both bluetooth and the Venue wifi (whatever that means). Yesterday I did an hour drive in the morning and used Google maps no problem. On the way home, neither Google Maps nor Wayz was connecting properly (kept getting the disconnect message mentioned in the other thread, but over and over and over which is unusual). The map screen even went white. So I disconnected bluetooth and it didn't help, eventually gave up. I also noticed during this time that the Venue wifi said "low data mode" on my iphone. What's that mean?

Anyway, this morning all seems well again - however I'm connected by wifi and not bluetooth (my iphone keeps saying it's not connected via bluetooth), however I was able to use google maps and text someone with my voice.

SO, my question is, are you supposed to connect via wifi only, or bluetooth, or both??