Fully integrated into BlackBerry Contacts, when the customer launches the app for the first time, WhatsApp can automatically scan existing phone numbers in the contact directory and extract the ones using WhatsApp, to help customers build out their contacts list and get started right away.

ENGADGET: WhatsApp lands on BlackBerry 10, offers Z10 owners a BBM alternative

Your mail-handling software would scan each message to see if either the sender's name could be found in your personal directory or a magic word could be found in the subject field.

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