Ah yes: another year, another new iPhone with another new chip at its heart. This year, there are two iPhones -- a 4.7-incher and a 5.5-inch model -- and they're both powered by what Apple's calling a "next-generation" A8 chip. But what can it do for you? Apple's saying it brings a 25 percent speed boost over the iPhone 5s' A7 chip, with a 13 percent size decrease (assuredly helping to keep the duo of iPhone 6 phones so svelte). As much as we like performance, we also like our phones to last longer than five hours -- what does the A8 offer in energy conservation? A 50 percent increase over last year, apparently.