There are 3 ways to project from iPad, iPhone (4 or later), or iTouch (4th Gen or later):

  1. vPresenter app ( available through  Apple iTunes app store) https://itunes.apple.com/us/app/viewsonic-vpresenter-viewsonic/id625064821?mt=8
  2. Use a VGA/USB or HDMI adapter to connect your device to a Viewsonic projector
  3. Use AirPlay Mirroring to project wirelessly to a compatible Apple TV device (view minimum requirements)  http://support.apple.com/kb/HT5209

To use AirPlay:

Double-tap the Home button at the bottom of your iPad or iPhone, scroll all the way to right, select AirPlay settings, and select the device you would like to project to (provided that both your AirPlay connected device and your iPad or iPhone are on the same internet network).