[HTC Rezound] pkopalek:
As long as you don't have partial wake issues, there are only two real concerns for battery.

It's not processor. Again, if the phone's not 'awake' while the screen is off, your phone's processor is not ramping up to full speed at all. While it's on and in your hand, 1.5ghz is a great speed for it to operate. Slower speeds than that significantly slow down how your phone operates, and you will have your screen on for seconds longer (Which uses WAY more battery than the higher clock speed).

In Facebook app, go to menu > settings > and change the refresh interval to NEVER!!!

As of Android 2.2, Facebook does push notifications. You don't need Facebook refreshing very 4 hours (OR EVER!). This wakes up your phone (ramps up processor speed, and so on), uses data (battery), and is unnecessary (since you get push notifications anyway). Turn that crap off. Same with Twitter. Turn it down to manual refreshing only (look in settings > accounts and sync as well as in the app). Same with Friendstream (which will automatically have its own refresh settings - fix them).

There are two things that use your battery.

1 - Screen. Turn your screen off when you're not using it. Stop turning your screen on every 12 minutes to 'see if you have any notifications'. Trust the green LED blinking light, or listen for your phone. You can stop checking it. You're using a TON of battery lighting up that 4.3" screen AND waking the phone back up (ramping up the processor, among other things, and it will stay awake for at least minutes, even after the screen goes back off).

2 - Data. Turn wifi off if you're not using it. Turn Mobile Network (GASP!) off when you're not using it. Pull down your notifications and hit Quick Settings, and turn Mobile Network off. Don't have that? Make the HTC Widget > settings > Mobile network. Turn it off when you're out with your friends after midnight. a) you're not going to post anything reasonable or coherent when you're out drinking anyway to Facebook, and b) call and text still works, so you can still mack on honeys all night (and text them drunkenly). You don't need your damn Gmail at 1am. I know you don't. Don't try to convince me otherwise.

If you keep your screen time to a minimum (and brightness down if you're not using auto brightness), and TURN OFF mobile network (internet) when not using it, your battery will last DAYS. Yes, the stock battery. Now, do you do 100+ texts per day? Sorry, your battery is going to die today. And tomorrow. Every day. The screen time murders the battery, and the Wake time that your phone will have as a result (like every time the phone lights up - for minutes at a time, it'll stay 'awake').

That's how you keep your battery going. On any android phone. Yes, an extended battery works great. I bought one (half price in a verizon store) AND got an EXTRA one for $4 (on amazon.com). Yes, it's for thunderbolt, but YES it's the same part number. It's running my phone right now. Keep it charged, and in your glove compartment. Your life will be better.

http://www.amazon.com/dp/B0055OTNK4/ref=pe_175190_21431760_C1_cs_sce_3p_dp_1

Go get it. Turn off your internet, and your screen. Trust your LED notification light. Stop using MMS Screen On. Your battery will last all day, every day. Unless you text a lot. Then, good luck.