That pretty much covers everything.Could be a variety of things:
- There is no (or poor) 3G coverage where you are but WiFi is available
- You are uploading/downloading a large amount of data and want to take advantage of the higher speed of WiFi - it consumes more power per second but can often be enough faster that a large download (e.g. 6MB) will actually use less battery power over WiFi
- You want to make/receive SIP/VoIP calls over WiFi (only a handful of services/apps to do this right now as far as I know)
- You want to do file sharing via FTP or similar over a home network or between a laptop and your phone
- etc......
That said, 3G is so good that I don't often find myself using WiFi. Kind of up to your own particular usage patterns but it's nice to have the choice!
Ok, So I want to be sure, if i use wi-fi it will not use my data plan. So it wont cost me more? I am trying to figure it out to make sure. I know there is a limit on the data plan, I tried to find a way to turn it off when I am connected to wi-fi. But I can find a way to turn the 3g off, thank Doug
Ok, So I want to be sure, if i use wi-fi it will not use my data plan. So it wont cost me more? I am trying to figure it out to make sure. I know there is a limit on the data plan, I tried to find a way to turn it off when I am connected to wi-fi. But I can find a way to turn the 3g off, thank Doug
wifi draws less power than 3G and it is faster...
3G (300kbps): 210mA * 2.7 min = 9.5 mAh
WiFi (1Mbps): 330mA * 48 sec = 4.4 mAh
What I get for that is that based on the time that the radio is active, the wifi draws more current from the battery, but since its faster the radio is using less battery doing a specific task due to a shortened duration.
And a "google developer" is likely a software guy, different radios in different devices will have different efficiencies.
3G (300kbps): 210mA * 2.7 min = 9.5 mAh
WiFi (1Mbps): 330mA * 48 sec = 4.4 mAh
you're right about active radio time. Are you aware of any devices with 3G and WiFi that are more efficient (in terms of time) on WiFi though? I'll admit different chipsets will be a little different, but it's probably negligible.
...from my own personal experience it seems that the wifi is more efficient overall than the 3g, but I have no data to support my feeling.