About WI-FI battery usage I keep reading about how much battery does WI-FI use, but when I look in settings > battery, WI-FI shows with &lt; 5% usage when I barely use the phone. And when I use it, the screen takes most of the battery and WI-FI doesn't even appear in the list! Does this mean I can leave WI-FI on all the time? Because 1-5% is not that much
I have the same experience with Wifi, I find leaving it on is much more convenient (your phone will prioritize Wifi over 3/4G, resulting in faster speeds and lower bills), and power consumption is negligible.

The only time when turning off Wifi conserve me some serious battery is back from my days with a Sony p990i, which runs UIQ3. Ah, old times...