iPhone 4S: Battery life, wifi on vs. off?

[benguild]

Does leaving Wifi turned on (but Bluetooth off) really decrease battery life that much? I've always only turned it on when needed, but with iCloud backups being automatic now I'm kind of tempted to turn it on all of the time.

 

[rick snagwell]

i think it sucks more out...due to the photostream always on, and iCloud backing up.

 

[benguild]

i think it sucks more out...due to the photostream always on, and iCloud backing up.

Right, would make sense ....
But, I'm wondering how much? I think photo stream operates over 3G, no?

 

[tollickd]

I know the iPad only does a back-up to iCloud when it's connected to the power. Is this not the same on the iPhone?

 

[benguild]

Right, but ... what if I want to just leave the wifi on all of the time. Will this affect battery? (even if it can't find a network)

EDIT: Apple does mention Wifi being on in the tests, but "ask to join network" was off (obviously) ....
http://www.apple.com/iphone/battery.html

Is this the intended functionality at this point?

 

[dialed1]

My 4S battery drains extremely fast with wifi on and not connected. WOW

 

[benguild]

What I'm wondering is ... can we leave Wifi on for minimal loss with the 5.0.1 update for convenience, or is this really going to just suck a lot of juice? I have 'search for new networks' turned off (or whatever that option is).

 

[mmmtastybusch]

leaving wifi on while not connected to a network definitely drains the battery faster. When it's not connected, it's always searching for a WiFi location

 

[cbronfman]

BUT if there is a WIFI network available

it burns the battery much faster if the phone is searching for a 3G signal or doing things over 3G if WiFi is turned off (and there is a WiFi available). I tend to leave mine "on" all the time although I realize there are times (like driving) when it would be more efficient to turn if off. I did find with my 3GS that the battery lasted far longer with WiFi on than when I had it off all the time and to eliminate the nuisance of changing it on or off, I just leave it on. I do leave BT off unless I know I want to use the headset.