However, despite the relaunch, some BlackBerry users said the app was not working.
The BBM was made available by BlackBerry on Google Play, Apple App Store and some Samsung App Stores for free, but for users who didn't pre-register to get the app, the must install BBM then enter their email address and wait for the rollout.
About 6 million people had pre-registered and could immediately use the app. BlackBerry originally scheduled the extension of the BBM to iPhone and Android phones on Sept 21 but stopped it after a few hours because an unreleased version of the app for Androids caused data traffic volumes to increase and affected the overall system.
The release is timely because it would help BlackBerry owners transition into new phones given the imminent collapse of the Waterloo, Ontario firm or takeover by interested buyers such as Fairfax Financial and Lenovo.