synchronizing apple mail

Do you have an iCloud account, do you have your mail account correctly setup on both devices. If you do, your mail should automatically sync.

What do you mean by "apple mail"? Are you trying to sync an iCloud/MobileMe email account or do you have a number of accounts in your mail program and want to sync them all? If the latter, you can only sync Apple icloud accounts, not others like gmail and personal domain email accounts. To do that, you need to define the mail account on each device if it is an IMAP account (POP accounts don't sync between devices, they only sync directly from server to each device independently).