This is a guide/help book to help people understand how to download the right BBM file and how to create a blackberry id and get your blackberry pin.
Blackberry Messenger has changed the entire landscape of communication industry and was exclusively available for blackberry users.
Now you can use it on android as well.
Please note: This is not the official guide but a tutorial created by me to help other users. I am not a representative of Blackberry.