How can I move my contacts from my MacBook Pro to my iPhone 4S?
Use your Mac Address Book and sync your iPhone with iTunes. From the Info tab, under Contacts, make sure to select "Address Book" from the drop-down menu before you sync.
I am not sure whether it works on Mac, but you can use copytrans contacts to transfer the contacts too (in case you do not want to use iTunes sync):
Finally, you can simply use the iCloud app and install it on your Mac. Make sure to enable iCloud contact sync on your iPhone. Then import contacts from your Mac to your iCloud application, this will move and sync the contact entries to your iPhone.
Make sure you're on ios5, then sign up for a free iCloud account. Enable it on all your devices (macs, pcs, phones), and your contacts will stay in sync automatically.
How to Transfer Contacts From Computer to iPhone
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