More than 20m people have downloaded and used BlackBerry's BBM messaging app on iPhone and Android smartphones in the week since it launched.
BlackBerry announced the milestone today, revealing that after 10m downloads in its first 24 hours, the newly cross-platform app picked up another 10m in the following six days.
The company says that BBM now has 80m monthly active users, with 60m on BlackBerry smartphones and 20m across iPhone and Android.
That's jumping the gun somewhat: while anyone who tries BBM in its first month on the new devices technically counts as a monthly active user, the real test will be if they stick around for longer. BlackBerry appears well aware of that.
"It is great to see so many people downloading BBM, but the true measurement for us is engagement – the connections being made and the conversations in which our BBM community engages," said BlackBerry's executive vice president of BBM, Andrew Bocking.
"The power of BBM has always been the active, real conversations and interaction that our customers enjoy. From here on out, we will focus on active users of BBM and will no longer focus on simple download numbers."
BBM's iPhone and Android versions initially used a virtual queuing system to restrict access to people who hadn't pre-registered their interest. BlackBerry has now removed this bar though, after a smooth launch week.
That's a far cry from the intended launch in September, when BlackBerry was forced to abandon its plans after a rogue version of BBM for Android leaked, causing problems for the service's ability to cope with increased traffic loads.
BBM has some way to go to catch up with WhatsApp, the current king of the messaging apps world. Earlier this month, WhatsApp said that it now has 350m monthly active users across all smartphones.