WMLongLife by the venerable and prolific developer Chainfire will make your device hop up from 2G to 3G when it thinks you need it and back down to 2G when you don’t, consequently keeping your battery level and sperm count high as resting on 2G, except under very unusual conditions, burns less fuel and emits less radiation than either using 3G or trying to jump to 3G chews up. When your phone is set for 3G but is on 2G, its fight to find and lock back onto 3G really punishes the battery. And when it’s set to 3G but doesn’t have a full signal, that’s when heavy power is spent and that’s when you really don’t want your phone on 3G unnecessarily. WMLongLife recognizes that there are occasions in your day during which 3G is called for, for instance if you start any applications you identify in the configuration as being worthy of 3G (like Opera and YouTube), at which points it will ramp up the connection. And when you either stop using the program or that program doesn’t appear to be needing 3G speeds for instance if the phone’s only using data either constantly or periodically for email, or if you start using wifi or plug into USB, it will pause data-using applications while ramping down to 2G to prevent any network error bubbles.
It’s a very sophisticated piece of software and it’s complicated to understand and describe to you everything that’s going on under the hood and as with radio management software your mileage may vary but it would be pretty strange if you installed WMLongLife and didn’t notice substantially improved battery life and there’s a decent chance that the brief delays of the software triggering your phone to jump from 2G to 3G, about five seconds, won’t be intolerable for what you get in return, especially if you tweak the configuration to suit your specific needs. To grab a copy hit his WMLongLife v0.65 thread on XDA but note that it may stop working on July 1st at which point you may have to throw down a few bucks (oh no!) to keep using it if he decides to go commercial or gets too fed up that not enough people are expressing their gratitude. Be advised this is beta software, though the odds are high that it is compatible with your WinMo phone (check the thread for a list). Yes it does do both GSM and CDMA.
Chainfire’s most famous for WMWifiRouter and if you want to see what else he’s up to check out his development blog. Even if you don’t care about battery conservation, if you’re at all intrigued by impressively designed software, WMLongLife falls under that category.