I was having poor battery life also, but after calling HTC technical support he told me to do a few things, and my battery improved quiet a lot, now i get easily 2 days out of it with moderate usage. I always have wifi on, and i only care about my email and calendar, which i check regularly throughout the day. I do occasional web browsing, msn, good amount of music via ear phones, and bit of news and games of an evening. Probably about 30 to 60 mins calls a day.
The htc tech told me to:
idisable the live grass background and change it to the dark HTC carbon fibre one, turne the typing vibration thing off (hint, you need to disable it under sound and also in language and keyboard, touch input, text input, vibrate when typing). Turn the HTC weather clock animations off, get rid of the exchange mail widget and calendar widget (easy enough to just have an icon to the real application on the desktop), change emails from push to every 5 mins (made a good difference), when indoors have screen brightness on a lower setting (i think about 25% is more than fine for indoors), and download advanced task killer ***BUT*** make sure that in the lists of tasks to kill, the task killer is also selected, as you do not want a task killer constantly killing apps that keep opening and starting up, that WILL drain the battery. It is only to kill the un necessary crap that starts up, curtsy of all the apps that you have downloaded and came with the phone. If the app is important it will open again and it is obviously needed. The only apps i have left unchecked (i.e. so they are not killed) are: messages, mail, calendar, java. When you turn the phone on, just open the advanced task killer and press kill. then the un important apps and the killer will close.
Also, make sure the only active sync things you have checked is your mail, then uncheck auto sync and uncheck background data. Then, open mail, make sure your email is set to check say every 5 mins, then using the HTC power widget, turn on the sync icon.
also, he said, as my phone was fairlly new, i should drain the battery, turn it off, fully charge it untill the light goes green, and keep charging for an hour. then turn on, use 50% of the battery, turn it off and fully charge it again. Fully drain that, then turn off and fully charge it.
All up, now i can go from 7am, over night and until about 6pm the next day with comfort on one charge. Before i could only get about 15hrs out of it, now im getting about 35hrs! With wifi always on, BT off, Sat off, screen dim, and 30 sec timeout. Try this and see how you go, it helped me.
