I leave mine on all the time, the battery drain is trivial.
When you have a weak carrier signal, your connection has to run at high power, that will drain a battery quickly. Wifi with UMA support eliminates that power consumption, as long as you are in a Wifi Hotspot.
If you have a strong carrier signal, you won't notice much difference.
I agree with the above about it being on vs off causing a minimal drain difference BUT you certainly will notice a data speed difference when using WiFi vs a 3g network. I never used it much myself until a few months back when I hopped on a hotspot for grins. Now if I am stationary I always do a scan to see if I can use a WiFi connection.
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That depends. Most places like hospitals, restaurants and car dealerships have an open system where it is as simple as enabling WiFi, doing a manual network scan and following the prompts to connect. Others have an open system but the first time you connect you will be directed to a website to accept a usage agreement upon connection. Lastly is security. Most use WEP so you enter a passcode when connecting. The passcode is maintained by the router/hotspot/access point administrator.
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3G is more of a battery hog, especially if you have a weak 3G signal. A weak wifi signal can also drain your battery fast to, this has been the case with all of my phones.
Some days i leave wifi on and use it all day and some days it's off and i honestly cannot tell any difference in battery life. If there is a difference it is very minimal, in my case anyways.
It tellin me I need a wep code I knw what the wep code means but does thus mean everytime I wanna use wifi I have to connect to the network with the passcode not automatically
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When I am at home and have a great edge signal I leave my wifi on all day, battery drain is minimal. Same as running with a good 3G signal. A weak 2G or 3G signal will drain my battery much faster.
If you save a network and its WEP code, the the next time you want to connect to it just turn on wIfi and wait a minute. Enjoy!
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The reality behind the battery drain always falls down on usage. If you use it a lot, your battery will drain fast, with or without wi-fi. If you know you're going to be away from a familiar wifi connection for a long time, then turn it off. Same with GPS. Unless you use it frequently, just turn it off.
With average use of my blackberry, I pull up to 2 days with wifi on.