But the others are also taking the technology to heart.
'If you are currently targeting the iPhone and Android with HTML5, it will be easy to add Ubuntu, as well," Canonical founder Mark Shuttleworth said in a video introducing his new OS.
But even if HTML5 is making great strides, RIM, Canonical and Jolla all feel there is a need for an alternative native development environment, as well. There is a common denominator here as well: using Qt.
Qt is a cross-platform application and user interface development framework for desktop, embedded and mobile applications that Digia acquired from Nokia last year.
Digia has been in contact with Canonical and Jolla, and has also worked closely with RIM on the BlackBerry 10 launch, according to Katherine Barrios, director of marketing for the Qt unit at Digia.
The use of Qt is a win-win situation; it solidifies Qt as a cross-platform framework, while Canonical and Jolla can take advantage of its more than 500,000 developers as they build their own ecosystems, Barrios said.
"It is definitely the right strategy. They have to minimize the barriers to entry, and that is what they are doing. Qt is established and HTML5 is still nascent, but there is the scope to reuse code from device to device," CCS Insight's Blaber said.
On HTML5, Blaber would like to see especially Mozilla, Canonical and Jolla working together to create as much consistency as possible for developers, he said.
However, regardless of how good the user interfaces are and the availability of applications, success will not come easy.
Ranking their chances, they can be split into two groups, with RIM, Mozilla and Tizen in the first and Canonical along with Jolla in the second, according to Strategy Analytics' Mawston.
Tizen ends up in the first group because it's backed by Samsung Electronics, but that could also turn into a disadvantage if other vendors perceive Samsung controlling it. BlackBerry 10 qualifies because of its known brand and existing global distribution network, while Firefox OS has support from the likes of Telefónica and ZTE, Mawston said.
Firefox OS can deliver a far better experience than Android at price points around US$100, according to the Spanish operator.
For Jolla and Canonical success will be even harder to come by.
"Above all they'll need hardware partners," Mawston said.
Since the newcomers were fairly quiet at CES in Las Vegas, the expectation is that Mobile World Congress will be a coming-out party for a lot of the new platforms, according to Blaber.
But for RIM's employees it's crunch time, and the company is looking forward to showing the world how good BlackBerry 10 is, according to Rob Orr, RIM's managing director for UK and Ireland.
"As you can imagine everyone is buzzing," Orr said via email. "We're working around the clock to ensure that every last box is ticked ready for launch."
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