Juicedefender helps when you are on standby. :)
I believe that battery life ultimately depends on how much you use your phone and what you use it for. UV or AVS helps out on moderate to low use. If you constantly hammer your phone, no matter what ROM your on or how much undervolted you are wont make a difference, typical smartphone problem. It's a USE to STANBY ratio I guess.
Originally Posted by hah2110
Using JuiceDefender and it CLAIMS I am saving >2x battery life but I don't see ANY difference. I also use advance task killer but I'll try automatic task killer.