The $399 iPad 2 boasts better battery life

That seemingly ordinary iPad 2 that Apple is selling for $399 has actually been modified internally in ways that, in some cases, can yield better battery life, according to a report. Along with the new third-generation iPad, Apple in March began selling a lower-priced, $399 iPad 2. Among those iPad 3 models is a variant, the "iPad 2,4," that sports a more advanced 32-nanometer version of the dual-core Apple A5 series chip, according to chip review site Anandtech. (The older iPad 2 uses an A5 based on a lagging-edge 45-nanometer manufacturing process.) And an A5 built on a more advanced manufacturing process yields improved battery life, according to tests done by the site. "The iPad 2,4's gains in battery life...are significant. We measured a 15% increase in our web browsing battery life, a nearly 30% increase in gaming battery life and an 18% increase in video playback battery life" compared to the iPad 2 with the older A5 chip, according to Anandtech. Finding one of these iPad 2,4 variants is not easy, however. "If you're in the market for an iPad 2, the 2,4 is clearly the one to get - if you can find one that is," wrote Anand Shimpi. The only way to know for sure is to open up the box. The iPad 2 variant may have iOS 5.1 preloaded. The older iPad 2 models -- which Apple still has in inventory and continues to sell -- may have 5.0.1 or older, Shimpi said. But the most accurate way to find out is by using a utility like Geekbench that will indicate whether it's the iPad 2,4, Shimpi said. As a chip's geometries shrink -- going from 45-nanometer technology to 32-nanometer technology, for example -- a lot of things can happen. All of them usually good. The chip can get more power efficient or faster or both, among other merits. And this is probably just the beginning. It wouldn't be outrageous to expect that the iPhone 5 would use a chip based on the same 32-nanometer manufacturing process.