FaceTime is a cross-platform video calling program exclusive to Apple brand electronics. It can be used on some iPod Touch models, as well as iPads, Mac computers and iPhone 4 devices. FaceTime is included with the iPhone 4, iPad and iPod Touch but requires an Apple ID for download on a Mac computer. FaceTime operates independent of whether an iPhone 4 uses a SIM card, as the only differences between SIM and non-SIM iPhone models are related to hardware.
Open the Contacts app. Select the desired contact and check that is has a valid iPhone 4 phone number (the only phone FaceTime works on is the iPhone 4) or Apple ID e-mail address. For devices without phone numbers, such as Mac computers, iPods or iPads, FaceTime calls them by using the Apple ID entered when the program was downloaded or first launched.
Open the Phone app and select the contact.
Tap the FaceTime button, then wait for the other party to accept the call. The video call will begin automatically.
Pull the iPhone away from your face to reilluminate the screen.
Tap the FaceTime icon on the call information screen.
Wait for the other party to accept the FaceTime invitation. FaceTime calls can only be established during a phone call between two iPhone 4s.