IMO for Blackberry is available if your BB runs Android OS, like the Blackberry Priv. For BB without Android OS, Imo Messenger is not available yet.
So you will have to wait for IMO for Blackberry Z3, Porsche Design P’9982, Z30, 9720, Q5, Z10, Q10, 4G LTE PlayBook, Curve 9320, Curve 9220, Blackberry Curve 9380, Bold 9790, Porsche Design P’9981, Curve, 370, Curve 9360, Curve 9350, Torch 9810, Torch 9860, Torch 9850, Bold Touch 9900, Bold Touch 9930, 4G PlayBook HSPA+,… but maybe in a near future, Imo will be launched for BB. We wait for it :).
Download IMO for Blackberry Priv (Android)