i phone4

Because your iPhone goes with you everywhere, you’re always ready to capture every moment. And with iPhone 4, you can do it in stunning high definition. Its advanced backside illumination sensor delivers great-looking video in both bright and low-light settings. And in dark environments, you can brighten the scene with the built-in LED light.
Now you can run your favorite third-party apps — and switch between them instantly — without slowing down the performance of the foreground app or draining the battery unnecessarily.* This smarter approach to multitasking is available only in iOS 4.

Listen to audio in the background.

Now you can listen to audio from compatible third-party apps while checking email, surfing the web, playing games, and performing other tasks. So when you want to follow a ball game or listen to music from Pandora, your productivity never skips a beat.

Keep GPS apps running.

Apps that use GPS can continue to run in the background. Not only do they constantly update your position, they can also give you spoken turn-by-turn directions even as you listen to music (the music volume lowers while the directions are spoken). It’s perfect for social networking apps, too. Now you and your friends can find each other even when you’re not actively using the app.