Comment 5 for bug 1373463

Yes, *using* Wi-Fi uses less battery than *using* cellular data. But that does not mean turning off cellular data manually would noticably save battery. If you're using Wi-Fi, the cellular data modem should be mostly asleep, waking up occasionally to check for MMS (the one thing Wi-Fi can't do). And Ubuntu Touch, probably unlike your current phone, is currently extremely strict on what apps can do in the background; a mail or Twitter app couldn't update in the background, for example.

Having said all that, a cellular data switch might be worthwhile, I'd just like to see some evidence. Every little thing added to indicator menus makes them a little more similar to System Settings, which makes the overall mental model of the phone a little more confusing.