Go to the contact tab, then press the "phone/message" icon in front of the desired contact, a menu will be displayed with the different actions allowed with the selected contact
Here is a short description of the different actions you can do with your contacts
Contact's actions
It gives you, the destination rate of BBeeout to call some one
It allows you, to invite someone
It allows you, to transfer credit, to a registered contact
It allows you, to call someone
It allows you to send message, to register contact