Battery Life on the iPhone 4 Lasts 38 Hours on heavy use. Yes, 38 hours!

We have a significant update to this post here.

Forgive me for being excited but if there is one major gripe I’ve had with the iPhone it’s battery life. I’ve bought battery case after battery case and external battery after external battery but have never been satisfied.

I even tweeted just a few days back that for its next release, Apple should focus on improving nothing but the iPhone’s battery life – call it the “iPhone Charged” or something.

With the release of this new iPhone however there seems to be some very surprising news. Three credible sources are reporting that their iPhone life has surpassed anything they have experienced with the iPhone before.

Engadget reports that – on heavy use – the battery lasted 38 hours. Mossberg claims that his battery didn’t even reach the red zone in his single day of tests (which means he must have been using it a fair amount.) Finally, Xeni Jardin at BoingBoing reports that with “3G data and WiFi turned on the whole time, she got a full 4 days of battery life!??

This is huge.

Now their exact quotes because I know I’d want them if I were you:

Engadget:

The battery life on the iPhone 4 has been outstanding thus far, exceeding our expectations for longevity during testing. We’ve only had a short time to use the phone, but in the week or so we’ve been carrying the device as our main phone, we’ve had pretty amazing results under normal to heavy use. In fact, we managed to squeeze more than 38 hours — yes, 38 hours — of life out of a single charge using the phone as we normally would. We’re talking calls, some gaming, lots of push email and calendar invites, playing music over Bluetooth in the car, and just general testing (like downloading new apps, rearranging icons, tweaking settings). We went from 10:30AM on a Saturday morning till 1:00AM on Monday without needing to charge the phone. Of course, it switched itself off just after the clock struck 1, but it was thrilling — like that episode of Seinfeld where Kramer and the car salesman see how far they can get in a car with the tank on E. Sitcom references aside, the battery life seems markedly improved in the iPhone 4, and why not? It’s got a much larger battery coupled with that iPad-powering A4, which has already shown that it can sip rather than gulp power.

Mossberg:

Apple claims longer battery life for most functions—seven hours of talk time, for instance, versus five hours on the earlier model. I didn’t perform a precise battery test, but, even in heavy use, the iPhone 4’s battery never reached the red zone on a single day of my tests.

BoingBoing:

With light use, but with 3G data and WiFi turned on the whole time, I got a full 4 days of battery life. With very heavy video recording and playback, instant messaging, email and data tethering over 3G, I got a full day of battery life. I didn’t have enough time before this review to do careful benchmark testing against Apple’s claims, so I can’t provide specific percentages, but it felt like the battery life was a good 20-25% meatier.

Apple promises up to 7 hours of talk time on 3G and 14 hours of talk time on 2G, Standby time of up to 300 hours, up to 10 hours of solid use on Wi-Fi, up to 10 hours of video playback, and 40 hours of audio playback.

Compare that with the stats promised for Apple’s iPhone 3GS: up to 5 hours talk time on 3G, up to 12 on 2G. Up to 5 hours of internet use on 3G, up to 9 hours on Wi-Fi. Up to 10 hours of video playback, and 30 hours of audio playback.