fruux is a lightweight and convenient system preference pane, that syncs your Address Book, Calendars, Tasks and Bookmarks between different Macs. fruux supports sync conflict resolution which will help you when you changed a record on more than one machine.

Features:

You won't forget this important phone number again
• Your computer: fruux contact syncing is natively supported by Apple Mac OS and also works great via third party apps like Mozilla Thunderbird (currently via a plugin) on many other platforms*.
• Your iOS device: fruux contacts syncing is natively supported by iOS devices like the iPhone, iPad or iPod touch. No need to download an app. Visit our special configuration URL and it just works*.
• Any browser: With the fruux web app you're able to access your contacts from anywhere in the world, even if forgot your phone and don't have your computer with you*.
• Your other devices: Because fruux is highly standards compliant, you'll have access to your contacts from any device that supports CardDAV*.
 
You won't be late to important appointments again
• Your computer: fruux calendar syncing is natively supported by Apple Mac OS and also works great via third party apps like Mozilla Sunbird or the Mozilla Thunderbird plugin Lightning on many other platforms.
• Your iOS device: fruux calendar syncing is natively supported by iOS devices like the iPhone, iPad or iPod touch. No need to download an app. Visit our special configuration URL and it just works.
• Any browser: With the fruux web app you're able to access your calendars from anywhere in the world, even if forgot your phone and don't have your computer with you*.
• Your other devices: Because fruux is highly standards compliant, you'll have access to your calendars from any device that supports CalDAV.
 
We'll keep you even better in sync than you thought
• Your Bookmarks: We're keeping your bookmarks in sync between all of your Apple Mac OS computers. If you added a bookmark in your office, you'll have it on your Mac at home, too.
• Your Mail Notes: fruux syncs your Mail notes between all of your Apple Mac OS computers.
• Widgets: We're actively working on tons of widgets and little apps that will help you automating many task you have to take care of manually at the moment.
• Third Party Access: With fruux you won't have to re-enter your data, when using third party web applications. Our APIs help other developers helping you. If you grant them access, you'll be able to work with your fruux data in their apps, too*.
 
Standards compliant, highly reliable, secure and trustworthy
• Standards compliant: We've built fruux from the ground up on open standards. That provides for high interoperability and gurantees that you'll always have access to your data.
• Highly reliable: The fruux cloud is powered by Amazon Web Services (AWS). AWS delivers a highly scalable infrastructure platform with high availability and dependability. Check the AWS case study about fruux for details.
• Your data is safe: Every transaction is secured with industry strength ssl encryption and our cloud runs on ISO 27001 certified and SAS70 Type II auditedAWS infrastructure.

* Works with CalDAV/CardDAV compatible devices.

Editor's Note: Further development is going to be limited to fruux as a web application.

Requirements:
fruux works great on Macs with MacOS X 10.6-10.8
Unfortunately machines with MacOS X 10.5 Leopard are only able to sync calendars
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