Witness requires Mac OS X 10.6 (Snow Leopard) or later.
The free iOS app is compatible with iPhone, iPod Touch and iPad and requires iOS 4.2 or later.

Changelog
Changes in version 2.1.2
  • Fixed an issue that automatically disconnected some Macs
Changes in version 2.1.1
  • Fixed an issue that prevented some Macs from automatically reconnecting after updating
  • Fixed a crash when retrieving the diagnostic messages
Changes in version 2.1
  • Witness is now using WebSockets, dramatically improving firewall compatibility
  • Witness reconnects more reliably when your internet connection drops
  • It is now possible to select a sound input source for videos
Changes in version 2.0.1
  • Fixed an issue that could prevent videos from being uploaded
  • It is now possible to connect 3 cameras to the same Mac
  • Fixed an issue that prevented the user agent from launching
  • Fixed a rare issue that caused Witness to appear in the dock
  • Improved logging and error handling
Changes in version 2.0
  • Sneak Peek: watch live images from any Mac in your alarm system
  • Auto-activation: use the location of your iOS device to automatically arm and disarm the alarm
  • Face detection: restrict motion detection to human faces
  • Motion detection sensitivity can now be adjusted for a specific environment
  • It's now possible to connect and use up to 3 USB or Firewire cameras per Mac, making it easier to protect larger areas
  • Applescript support: it's now possible to have AppleScripts executed when arming and disarming the alarm, or when motion is detected
  • Witness can now automatically update itself
Changes in version 1.2.2
  • Fixes issues with activating and deactivating the alarm on some Macs running Lion
Changes in version 1.2.1
  • Fixes issues with the Mac OS X screensaver lock screen on Lion
Changes in version 1.2
  • Witness is now ready for Lion
  • Added support for Creative Live Cam Socialize HD webcam
  • Reduced CPU-usage on some MacBook models
  • Fixed an issue that in some cases caused Witness to restart during long periods of surveillance
Changes in version 1.1
  • Added support for the Blue Eyeball 2.0 camera
    Please note that this camera model is more sensitive to changes in lighting, so it is recommended not to point the camera towards a window
  • Fixed an issue that prevented password authorization when the alarm is armed while the screensaver is already running
  • Fixed a bug that caused the menu bar icon to freeze
  • Fixed a bug that enabled the user to bypass the lock screen without entering a password in certain conditions
  • Fixed a bug that caused the screen saver password settings to change
  • Improved background service reliability
  • Fixed issues with signing in using the preference pane