The 5 million figure is based on the amount of users who have accounts that have been activated, its likely the number could be much higher if there are still users waiting for access. Blackberry hasn't given any information as to how many users are still waiting for activation or whether there are any at all.
BBM has received favorable reviews so far among users with a 4+ star rating on both platforms. Reports say it quickly became the number one free app on the App Store upon release.
While the numbers are good, they likely aren't enough to save the company from its decent from relevance. Many have suggested the cross platform BBM app could have been a smart move in the past, but with players like WhatsApp gaining more and more ground every month, BlackBerry has what seems like an impossible amount of catching up to do.
This morning at Nokia World 2013, WhatsApp CEO Jan Koum announced that the service now has 350 million monthly active users, up 50 million from August. Koum also said that WhatsApp sees more than 7 million users per month register for the service through Nokia devices alone.
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