Tap (or speak) to call.
To make a call on iPhone, tap a name or number. That’s it. You can tap to call from just about anywhere: a name in your contacts list, a number on a website or text message, even a phone number on a map listing. Voice Control lets you speak a name or number to make a call. And you can switch between calls, merge calls, or add up to five callers with a tap.
Hear and be heard, even in loud places.
Making a call at the ballpark, in the airport, or on a crowded bus can be frustrating, if not downright impossible. But not with iPhone 4. It includes a microphone built into its top edge and uses sophisticated audio technology to suppress unwanted background noise. The technology works on everything from crowd noise and engine sounds to music and loud conversation — even just a few feet away. So the person you’re talking to can hear what you’re saying, not what you’re hearing.
Talk face to face.
Sometimes you want to see who you’re talking to rather than just hear them. With FaceTime, iPhone 4 lets you do exactly that. Just tap the FaceTime button from a Contact or a phone call to turn your conversation into a live video call with another iPhone 4 user over Wi-Fi. Then you can share a smile or wave hello with friends and family, even when you’re thousands of miles apart. No other phone makes staying in touch this much fun.

See your voicemail.
Visual Voicemail on iPhone is still the biggest breakthrough in voicemail since, well, voicemail. It lets you view all the messages you’ve received and select the one you want to hear first — just like email. So instead of listening to messages in the order they were received, you can go directly to the messages that are most important to you. To return a call, just tap the Call Back button.
Do more with your contacts.
The Contacts app on iPhone is more than just a list of names and numbers. Tap a contact’s address and iPhone opens Maps so you can get directions. Add photos to your contacts and see your friends’ faces when they call. Scroll through names with a flick, or search to find someone fast. And sync all your contacts by connecting your iPhone to your Mac or PC, or wirelessly via MobileMe, Microsoft Exchange ActiveSync, and CardDAV-compliant servers.