Not on my Android phone, a Motorola Moto X Play. Wifi is by far the largest battery hog.

lol man. thats because it is used the most. in order to determine which uses more energy you would need to run a series of controlled tests where you transfer specific amounts of data over time with one radio or the other.

I did do that. Using my phone normally, it uses a lot more battery to have wifi on.

I have a generous data plan, so I don't need to use wifi to preserve it.

I don't have a data plan so I always have mobile data off.

That's a pretty rare use case, and not one that I expect most smartphone makers to optimize for.

That doesn't turn off your LTE radio though...

But djrogers was saying that if I had WiFi on it'd save power because LTE would be off. Surely they only mean the data component?

I thought the basic mobile connection was active all the time (unless there was no signal). Are you saying if I turn WiFi on, and I receive an SMS (not through iMessage) or a phone call, it's actually coming through WiFi and the mobile connection is totally off? Surely not.

It’s possible, depending on your carrier, that it uses Wi-Fi for calls, but doubt that’s what he meant. Either way, in your specific use case, I agree, turning off Wi-Fi would save power, I just don’t believe it’s 2x difference though.

I just looked it up and found the official page on Wifi calling[1], but yeah, that option isn't there on my phone.

[1]https://support.apple.com/en-nz/HT203032