I've been using my phone all day: I took a dozen pics or more, some video, sent emails, posted to the internet, chatted via IM from my taxi, played with settings, showed off games to co-workers and, of course, made and received several long phone calls. And my battery now at the end of the day? 100%.
How? What happened to my opinion several days ago that the battery life suuuucked on the Nokia? Well... I stopped being stupid. It's AMAZING the things you can accomplish once you do that simple thing.
In my eagerness to try everything when I first got the phone, I turned everything ON. It dawned on me after my disaster at the dentist's when I didn't have any battery left at the end of the day when I needed it, that maybe this is a bad idea. So I turned everything OFF (and one thing ON), and poof, longer battery life. Wow, hey?
When I say "everything" what I'm really talking about is the things that you control:
- Light Sensor: Menu -> Tools -> Settings -> Phone Settings -> Display -> Light Sensor. Set it to Maximum, this adjusts the brightness of the screen and saves energy in bright areas.
- Screen Saver Timeout: In that same options menu, I set the screen saver timeout to the lowest, so after 1 minute, the screen goes dark (i.e. pretty much immediately)
- GPRS Connection: Menu -> Tools -> Settings -> Connection Settings -> GPRS -> GPRS Connection. I set it to "when needed" I suspect that this was the main energy-hog culprit. But since it only takes about 20-30 seconds to connect to GPRS when I need it (and pretty much needed the same, even when it was supposed to be connected anyways) there's no reason to have it polling for a GPRS connection all day.
- Bluetooth: Menu -> Tools -> Connect -> Bluetooth. Turn it off if you don't need it. Since my PC at home is the only device I know of that talks Bluetooth right now besides my phone, there's no reason to have it on all day. Like GPRS it's just sending out signals all day, draining the battery, for sure.
So there you go. Be smart and have longer battery life. Works for me.