I seriously can't believe the piece of $$it battery they equip these with. Mine is basically in the charger most of the time. Yes I do use it for Internet quite a bit, but still. What a joke. it's no better than my previous 3G was.
Are you running a lot of apps in the background? I had Skype installed and noticed that it drained my battery really fast. Once I deleted the app, I was back to normal which will easily get me through the day.
I do not work for Apple nor am I any kind of fanboy. I've had a Nexus One, 3GS, Treo 800w, Sprint 6800, Sprint 6700, Motorola Q, BlackBerry Bold, and BlackBerry 8130. The Treo had the best battery life (early on - it's not really as good any longer), and maybe the 8130 next (although the battery started degrading rather soon into the first year). But the iP4 lasts longer than my previous "big screen" devices easily. And it gets used more than my other non-iPhone devices. Just my experience. YMMV obviously, and apparently it is. (Additionally, the Moto Q was the worst followed by the 6700 and 6800.)
But how do you backup that statement? An independent test?
I own or have owned pretty much any "good" smartphone that comes out. So I am basing my statement off of comparing the battery life to all other phones I use or have used.
I could say that my Bold 9700 battery lasted longer, but then again, I didn't use it half as much as I use my ip4. I'm seconding the comment that you have an app that's draining your battery. I've had mine off the charger since 7 am. It's 10:14 pm and I've used it heavily and have 24% battery left. LOVE this phone!
The iPhone 4 has the best battery life of any smartphone. Easily.
Negative. I loved the BlackBerry battery - I could go a day and a half before it even reached yellow. I'm plugging up my i4 at least once a day to recharge it. It's definitely better than my 3G and 3GS, but def not the best smartphone battery on the market. I haven't tried a wide variety of smartphones in my past (Blackberry 7100g, Palm Treo 680, Moto Q9h, HTC 8900, HTC 8925, Blackberry 8310, Blackberry 8900) and from the ones I have tried - Blackberry has always been the best in battery usage.
I don't like the battery on this device, but it's not a major issue with me, it's decent enough to get by.
My iPhone 4 is at 75%, I plugged it off at 07:00 and phoned with it, wrote a lot over whatsapp or eBuddy, wrote some emails and even surfed on the web..., so after 9 hours only 25% less...