[Jeroen7]

I just got an apple watch series 2 and was wondering, is it more efficient to use wifi only if you have a wifi connection than bluetooth?
The watch seems to prefer bluetooth as if both are available. But is it not slower and drain more the battery of your watch and phone?

What do you think?

Are there more differences?

[Mac Guy]

Apple says the iPhone uses BT when possible because it's less of a drain on the battery than WiFi.

[tcuprof]

Apple says the iPhone uses BT when possible because it's less of a drain on the battery than WiFi.

And you don't have a choice in how your watch communicates with your phone.

[Mac Guy]

Strictly speaking, you can shut off BT or WiFi and your Watch will still function. Off the top, I don't know what features or functions other than Internet related stuff, will stop working if you're on one or the other. Working with WiFi off assumes the Watch is in BT range of the phone.

If enabled with a cellular radio, you could turn WiFi off, but you might get the same iPhone nag— "GPS works better with WiFi on..." or something similar.

[Jeroen7]

If you turn off your Phones bluetooth, the watch will try to connect via wifi if they are both on the same network.
I was more wondering if there is a big difference in power consumption there. Wifi takes more energy but is also faster than bluetooth (I think).

And you can just turn of your entire phone and the watch, if on wifi, will function for some things like messages.

[Mac Guy]

I was more wondering if there is a big difference in power consumption there.

Apple seems to think so. That's why the Watch uses BT by default.