Some of the biggest power drainers: GPS, Wifi, and Bluetooth.

In general, it is best to keep these services off unless you are using them. However, GPS will only be used when an application calls for it, so you could technically leave it on all the time.

Some other tips:

• Lower the screen brightness
• Turn off 3G (if you have a phone that you can switch between 3G and 2G).
• Disable automatic Data Sync or:
• Set your apps to sync at longer intervals or don't use apps/widgets that do synchronize often
• Turn off any unnecessary vibrations or haptic feedbacks
• Disable the keyboards backlight
• Avoid using the speakers, opt in for using headphones
• Underclock the CPU (rooted users)
• Turn off data completely (using an app like APNDroid)
• Don't use task killers to automatically kill off processes. They simply will respawn. Uninstall undesired apps.
• Use applications like Locale or Tasker to control your phone's Wifi/GPS/Bluetooth/Sreen brightness/etc. settings automatically with profiles that activate under certain conditions
• Set your screen timeout to a short time interval. Then use screebl to keep your phone screen on when the phone is only held at certain angles.

Some of the biggest power drainers: GPS, Wifi, and Bluetooth.

In general, it is best to keep these services off unless you are using them. However, GPS will only be used when an application calls for it, so you could technically leave it on all the time.

Some other tips:

• Lower the screen brightness
• Turn off 3G (if you have a phone that you can switch between 3G and 2G).
• Disable automatic Data Sync or:
• Set your apps to sync at longer intervals or don't use apps/widgets that do synchronize often
• Turn off any unnecessary vibrations or haptic feedbacks
• Disable the keyboards backlight
• Avoid using the speakers, opt in for using headphones
• Underclock the CPU (rooted users)
• Turn off data completely (using an app like APNDroid)
• Don't use task killers to automatically kill off processes. They simply will respawn. Uninstall undesired apps.
• Use applications like Locale or Tasker to control your phone's Wifi/GPS/Bluetooth/Sreen brightness/etc. settings automatically with profiles that activate under certain conditions
• Set your screen timeout to a short time interval. Then use Screebl to keep your phone screen on when the phone is only held at certain angles.