Push Accounts

MobileMe, Microsoft Exchange, and Yahoo! Mail are known as “push” accounts. When new information is available, such as the arrival of an email message, the information is automatically delivered (pushed) to your computer or to iPhone. (In contrast, “fetch” services require your email software to periodically check with your service provider to see if new messages have arrived, and then request them to be delivered.) MobileMe and Exchange also sync your contacts, calendars, and bookmarks (MobileMe only) in the same way. For example, if you add a contact to the address book on your computer, the new contact is automatically pushed to iPhone as well as to any other computer or device configured with the service.

Synced information is transferred automatically over your wireless connection; you don’t need to connect iPhone to your computer to sync. If you don’t have a cellular connection, iPhone can receive pushed data over a Wi-Fi connection when iPhone is awake (the screen is on, or iPhone is connected to your computer or a power adapter).