BlackBerry Messenger application is dedicated to owners of BlackBerry smartphones that offers instant messaging features (akin to Yahoo Messenger, Google Talk or AIM).
The interconnection of users is based on the unique PIN of the BlackBerry (beware not to be confused with the SIM card PIN).
This PIN is printed on the box so that the phone came under the phone battery and can be found in the phone menus (Options -> Status).
The interconnection can be made only by those who are connected via BlackBerry BIS / BES Internet.
BlackBerry Messenger can be downloaded free from this address , or the BlackBerry World app.
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