Apple has released a new version of its OS X Mountain Lion developer preview, which adds a new feature that helps protect a user's contacts book from apps on the computer.
The OS now asks users to grant permission to apps that want to access their contacts book - be it an email client, Skype or some other service. They won't do so until the user says "yes" to data being shared with a third party.
The move has presumably been made in response to the debacle Apple has experienced with iOS apps, such as Path on the iPhone. It, and others, have been raiding iPhone users' address books to then market to a third party.
It should mean that users will be more aware of which application has access to what data on their computers.
Apple, it seems, is keen to show that users will have greater control over apps and the apps they download in the future.
OS X Mountain Lion also features a new system called Gatekeeper that is designed to protect users from downloading apps that aren't what they seem.
Apple has said that it expects OS X Mountain Lion to be released in the summer.