Android an' Droid Top Battery Lasting Life: Droid X, Dell Streak and Droid 2, Says LaptopMag

DROID X Batter.gifBattery life on Android smartphones can be sucked out in a very short time. Battery life has been such a draining issue. There is nothing a user can do to change the functionality of the battery itself, although you can buy more then one and them switch them out.

Laptopmag published an article testing Android smartphones, the best bettery life was 
  1. Droid X at 7:42.
  2. followed by the Dell Streak at 7:35.
  3. Motorola Droid 2 at 7:07.
  4. Samsung Epic 4G 5:34.
  5. HTC EVO 4G at 5:27.
  6. Samsung Vibrant  at 4:44.
  7. Samsung Captivate at 4:43.
  8. HTC Droid Incredible at 4:33.
Their testing used app-killers, kept screen brightness at 40%, turned off Wi-Fi, Bluetooth, location and auto sync, the screen was on at all times, Flash and web plug-in were off, and the phones were in 4 bar service area. AMOLED phones used more battery power.  AMOLE used the most power when displaying white, therefore your homescreen should be set to a black background.
The test does not mirror real Android use, if you have different features enabled you may find that your battery doesn't last as long.  That's way you should figure out the tips that work for you best.
Reviews of Android Smartphones mentioned in this Article.