Originally Posted by boteman
I have left my Nexus on battery all day to see how long it lasts. It seems that when it goes to sleep it drops the WiFi connection because when I wake it up the WiFi icon pops in the status bar after a second, white, then turns green if I do something that exchanges data.
I have an HTC Hero to experiment with that I think does that also, so I guess that's just an artifact of the phone going to sleep and conserving battery power if it isn't actively using the data connection.
By default, wifi sleeps when the screen is turned off, hence using 3g or 4g for data. Most of the time this uses more battery. I'd suggest go into wifi advanced settings and setting the wifi sleep policy to never so it will stay on wifi when the screen turns off. With a decent wifi signal, that will save battery life when the phone is on standby.