Camera-A and Camera-B

• Camera-A is a paid iPhone application that allows you to transfer photos and images between iOS devices. All devices must have Camera-A installed to receive images, though the accompanying Camera-B application allows you to send photos for free from your iPhone. By installing the Camera-B app on your iPhone and Camera-A on your iPad, you can send photos and videos from the iPhone's cameras directly to the iPad via Bluetooth.
  
  

Chopper 2

• "Chopper 2" is a universal game for the iPhone and iPad, which puts you in control of a helicopter gunship as you fly around the screen shooting enemy soldiers and vehicles. Installing the game on your iPhone and iPad allows you to view the action on the iPad's screen while using the iPhone as a wireless controller. The connection is made via Bluetooth and uses the iPhone's touch screen or motion controls to maneuver the gunship on the iPad.
  
  

Walkie-Talkie

• Although the iPad hardware does not support cellular voice calls, it does have a built-in speaker, microphone and wireless connectivity options. The Walkie-Talkie application allows you to establish a Bluetooth connection between an iPad and iPhone, and send real-time voice messages between them. There is no charge attached to talking over Bluetooth between the iPhone and iPad, and the application also works with the fourth generation iPod Touch.
  
  

VoIP Apps

• Skype is a free voice over Internet protocol application that works on the iPhone and iPad. By installing Skype on both devices and signing each one into a different Skype account, you can make voice and video calls between the devices over the Internet. The native FaceTime application built into iOS devices provides the same function, as do applications such as Tango, Qik Video and Fring. An Internet connection is required to use VoIP services, and a forward-facing camera must be present on both devices for video calls.