So, BlackBerry Messenger  better known to the "youth" as BBM  is coming to Android and iOS. Excuse me while I digest the irony of that.I've had a PlayBook for the best part of a year and a half now. As you can imagine, one of the first things I checked for when I first loaded up the 7-inch device was BBM, if only to see what all the fuss was about.But BBM wasn't there. Indeed, even to this day, BBM is missing in action.I seem to remember that, in reply to customer queries, BlackBerry  then known as RIM  put out statements suggesting that the tablet's OS was incompatible with a BBM designed to run on BlackBerry's then mobile OS, BB7.Yet it now appears the messaging platform - which at its peak was credited with building BlackBerry into one of mobile's biggest brands - is now compatible with some of BlackBerry's biggest rivals, if not all of the firm's own devices.Ignoring the annoyance this has caused me and other PlayBook owners (and, being relatively few in number, that's not all too difficult), BlackBerry's decision to expand BBM is both interesting and encouraging on two counts.Firstly, it means BlackBerry no longer considers BBM a tool that can draw consumers to the brand on its own, and secondly, it makes you wonder what else the company will look to bring to rival platforms.Taking a logical view, it's not difficult to work out why BBM is hitting other operating systems.Its userbase has been steadily declining since major cross-platform messaging tools such as WhatsApp hit the scene, currently standing at 60 million users  that's somewhat behind the 200 million monthly users the aforementioned WhatsApp can boast.BlackBerry's PlayBook is still without BBMCross-platform messaging tools are also now the norm. Apple's iMessage aside, it's hardly a surprise that Microsoft hasn't limited Skype to Windows Phone and Google allows apps across all major mobile operating systems to plug into GChat.Consumers have friends that span multiple different handsets running scores of different operating systems. Most simply won't tolerate messaging tools that don't cross those same boundaries with them.The big different between BlackBerry and chat tools from other OEMs and platform holders, however, is that  in the cases of Skype and GChat  none of them are the backbone of their owner's businesses.BBM for a long time, however, was a key part of BlackBerry's offering.Even to this day, if you challenge a BlackBerry consumer to explain their loyalty, they'll throw the platform's physical keyboard, secure email and BBM right back at you.BBM undoubtedly still has enough of a brand presence to seriously challenge the likes of WhatsApp when it rolls out on iOS and Android (the decision not to support Windows Phone an interesting one, given the two are currently in a tight race for third place) in the months ahead.Nevertheless, the decision is an interesting one not because it doesn't male sense, but rather because of the company that's made it.The wall that BlackBerry built around its former market leading brand is slowly being taken down, brick by brick. First the company opened up to Android apps. Then CEO Thorsten Heins raised the possibility of selling off its hardware division , with software becoming the focus.Now, following the BBM news, I'm left wondering whether the company would also consider opening up its secure email services to other platforms. Is it technically viable?It certainly seems to make more sense to me than many of the company's current strategies.I've been especially vocal in my feeling that BlackBerry and gaming isn't a natural fit . In my view, the company reluctantly begun courting developers simply because that's what its rivals have done, and that's what it thinks consumers want.However, while the BlackBerry Z10 appears as slick and sleek as any smartphones out there (based on my own somewhat brief interaction with it to date), I wouldn't be surprised if the more 'traditional' keyboard-based Q10 ends up outselling it by some distance  UK retailer Selfridges has already claimed its the fastest selling consumer device its ever sold And playing to its strengths is, I think, the strategy BlackBerry is slowing moving towards.There's still massive demand in my experience for decent phones that feature a keyboard, and BlackBerry has been left with the space all to itself after rivals quickly moved to touchscreen only models.What's more, in a world dominated by increasing fears over web security, BlackBerry's approach to email is also a major strength.Apple's unlikely to allow BlackBerry to make a move on iOS in this regard, but a BlackBerry-branded email service on Android  viewed by some as a platform far too open for its own good - would undoubtedly be able to find a market.The BlackBerry Q10 appears to be proving popular in the UKSo, how about this for a strategy? What if BlackBerry switches focus to become a service rather than a walled of mobile platform?How about BlackBerry makes builds on its reputation for delivering secure communications and brings its tools to force across other smartphone platforms? And what about if its moves away from touchscreens and, instead, focuses on QWERTY handsets like the Q10 and newly announced Q5?As things stand, BlackBerry is allowing its competitors to dictate the rules of the fight, and naturally they're keen to square up in the arenas where they're strongest.For me, the Canadian company's longterm future will depend on its ability to impose its own strengths and to bring the market back towards it as a result.On that score, a multiplatform BBM may just be a sign that BlackBerry has finally starting to get the message.