"In the next few hours, people will start seeing BBM in Google Play, the App Store and in select Samsung App Stores - where it will be free to download," BlackBerry EVP (BBM) Andrew Bocking said in a post on the company's official blog late on Tuesday night.
In September, BlackBerry had paused the global rollout of its instant messaging service BBM on rival phones, blaming the delay on issues caused by an unreleased old version of BBM (BlackBerry Messenger).
The demand for BBM on Android and iPhone continues to be amazing. About six million people signed up for information about BBM at BBM.com, he added.
Bocking further said: "As you know, in just seven hours, about one million Android users were using the unreleased version of BBM for Android. What you don't know is that more than one million people have found creative ways to 'side load' BBM on their iPhone. This is incredible.
"To help manage this unprecedented pent up demand for BBM, we are implementing a simple line-up system to ensure a smooth roll out."
BBM is an Internet-based instant messenger app available on BlackBerry devices that allows messaging between BlackBerry users.
"Our team of developers and engineers has been working around the clock to bring you BBM - and make some upgrades while we?re at it - and some incredible work has been done," he added.
BlackBerry, however, said that those who signed up at BBM website will be able to use the app immediately.
"If you are among the millions that took the time to sign up at BBM.com, you can start using BBM immediately without waiting in line. If you didn't sign up in advance, don't worry - we are focused on moving millions of customers through the line as fast as possible," Bocking said.
BlackBerry had also announced in September that it has reached a tentative agreement for a USD 4.7 billion buyout by a group led by its biggest shareholder, Fairfax.
Earlier this month, BlackBerry co-founders, Mike Lazaridis and Douglas Fregin, evinced interest in acquiring the struggling smartphone maker. Both the co-founders have entered into a preliminary arrangement for bidding to acquire the Ontario-based firm.