iPhone to have better battery life, upgraded surface

Apple said today that when its iPhone ships June 29, its battery will deliver eight hours of talk time, up from the five hours Apple said it would have in a preliminary report that came out in January.

The increase to eight hours would bring the iPhone "closer to other cell phones," said Jeff Kagan, an Atlanta-based independent analyst. "Battery power is one of many key items customers look for. Nobody wants a dead phone, even if it is the coolest new item on the market."

Apple also announced that the entire top surface of the device, including the 3.5-in. display, has been upgraded from plastic to optical-quality glass to resist scratches and to improve clarity.

The durability of the touch display has been a concern among some potential iPhone users as the device is controlled with a "tap, flick, or pinch of the fingers," as Apple puts it.

According to Apple research, four other recently released multifunction devices all have plastic screens: Nokia's N95, Samsung's BlackJack, Research In Motion's BlackBerry Curve 8300, and the Palm Treo 750.

Apple also said the iPhone's battery will support six hours of Internet use, up from five hours in the January estimate; seven hours of video playback time, up from five hours; and 24 hours of audio playback time, up from 16 hours. Standby time will be 250 hours, Apple said.

"With eight hours of talk time and 24 hours of audio playback, iPhone's battery life is longer than any other smart phone and even longer than most MP3 players," Apple CEO Steve Jobs said in a release.

Apple didn't describe what enabled the increase in battery performance in its official statement, but a company spokeswoman said the January numbers were "preliminary estimates." When asked if Apple had re-engineered its power management software to save power, she said, "Certainly," but declined further comment.

Kagan added a caveat, noting that people who buy iPhones will be using them more than other people use traditional cell phones. "The screen is cool to look at and begs you to touch it and play with it," Kagan said. "All that time sucks the battery dry. We have to see if this extended battery [time] is enough."