Extending your iPhone's battery

The battery life on my new 3G is a joke. My Treo 700wx would last two days and I had GPS services and push Exchange and Gmail email. Slingbox TV, etc.

I'm working like crazy to get the iPhone to maintain a charge past 4:00 in the afternoon. Turning off this and that. Guess what, if you have to disable all the features to get battery life to an acceptable level then it really isn't a very "cool" phone anymore, now is it?

It's typical Apple hype, make an OK product but sell it as "Sex in a Bottle". Everytime I buy another of their products I find that it has just as many problems, if not more, than their competitors. I wish I still had my Treo.

I find it better to turn down the brightness however... why do you want to conserve your battery... if you do your iphone will die a month after your apple care is over
i say use it to its full extent and then get a fresh one from apple before apple care runs out?

Here is was REALLY helped my iPhone 3G battery... A LOT! AND I even KEEP 3G ENABLED!

1) Turn push mail off. Set mail to fetch at 1 hour intervals.
2) Turn WiFi off when not needed.
3) Turn Bluetooth off when not needed.
4) AND... This one is VITALLY IMPORTANT: when you find yourself using GPS, you MUST go into settings and turn Location Services OFF AGAIN! This is a major bug and hopefully Apple fixes it soon. This 4th step is the one that saved me. It meant the different between having my battery drained before lunch - to having it at at about 90% capacity at bedtime!

Purely anecdotally - the one thing that made more difference for me than anything else was turning the brightness way down.

Since I updated the firmware I have much better battery life and better G3 and wireless performance:

A must-do if you have the 5A345 firmware (probably true for all early adapter who already have a G3...)

http://discussions.apple.com/thread.jspa?threadID=1617981&tstart=45

My setup, 3G on, Wifi off (except at home), Location Services On, BRIGHTNESS at about 25%, auto brightness off, and I'm still at about 50-70% battery at the end of the day. I use it a bit, and have had a couple of days where it was at maybe 20% at end of day, but I am seeing no problems with battery life. I used to have a TMob Dash, and am using my iPhone way more, and the Dash would be dead by 5pm.

It would be nice if Apple added simple, customizable energy-saving settings like on their laptops. A button for "Better Performance" or "Better Energy Savings" as a toggle right at the root of settings. Right now, saving power is a bit of a pain because all these energy-sucking features are all over the place in Settings.
How about a customizable setting, where I could turn a few things off or on then save that setting, making it easy to access in one tap?

BossPrefs in Cydia (jailbroken 2.0 software) is a great way to change some of these settings quickly.

It appears in the attached link that Apple chose an optimum amperage to allow for high-capacity as well as greater cycles.

I turned off this feature, and while visiting a friends house I got a pop up that said

"Incorrect Wi-Fi Password"
Enter the password for
"NETGEAR"

I have never logged in to a wireless network at his house, nor have I ever logged in to a NetGear router. I seriously doubt turning off notification saves battery life, it is apparently still scanning for networks.