——-UPDATE——-

Apple has done away with the dreaded Sync Services … HURRAY!

In the old days (in the technical world that could mean a month ago) you had one calendar and contacts application such as Palm Desktop, one portable device such as a  Treo and you synced them together through what is known as a conduit.  For the most part this worked.  However the challenge was that your information was restricted to just those two locations; your Treo and and your one application.

In order to synchronize your data to more than two locations, Apple created Sync Services.  Sync Services is system and a database, called the Truth database, that keeps a copy of all of your contacts, tasks and calendar items and knows which is the most current information.  There are applications which natively connect with Sync Services: Address Book, iCal, Daylite to mention a few.  The iPhone connects via iTunes, Palm and other phones connect via iSync and there are two common third party sync services conduits that allow other phones, PDAs, blackberries etc. to connect to Sync Services.  They are Missing Sync and Pocket Mac.

When you add a contact to Address book, Sync Services automatically sends that information to the Truth Database.  When you sync your iPhone, the iPhone looks for any changes between what it already has and what is listed in the Truth database.  Whichever is the most current information, based on modification date and time, becomes the “Truth” and is then sent to all applications and devices which are connected to sync services.  If there is ever a conflict that Sync Services can not resolve, an application called Conflict Resolver notifies you of the potential conflict and asks you how you want to resolve it.

If you have a MobileMe account and have setup your iPhone to wirelessly “Push”, your contacts, tasks and appointments will be automatically sent from the Truth database to MobileMe and then to your iPhone over the air.  To learn how to setup MobileMe click here.