The makers of the ubiquitous BlackBerry announced a $150 million innovation fund today, the latest salvo in the growing battle of mobile “platforms.” Research in Motion, the Waterloo, Ontario-based maker of the BlackBerry, joined with Canadian bank RBC and publishers Reuters Thomson in announcing the BlackBerry Partners Fund, which will finance projects to create applications for the hand-held device that is a favorite of corporate and financial executives.

RIM’s move is a response to the recent $100-million fund announced by Silicon Valley VC Kleiner Perkins to spur application development for Apple’s iPhone. And of course, that follows Google’s announcement several months ago of Android, a standardized operating system for smartphones and other hand-held devices and a $10 million kitty to support developers. In each case, the goal is to create a so-called platform that will essentially be a dominant operating system that will attract handset makers and developers. But creating a successful platform doesn’t guarantee you’ll make money.

Last week, Google announced it would invest $500 million in a joint $32.2 billion effort by Intel, Comcast, Time Warner and others to spur the faltering Clearwire wireless broadband service. Clearwire, which is committed to creating a national network using WiMax, faces competition from 3G technologies and new high-speed technologies like LTE embraced by Verizon, AT&T and others. In return, Clearwire has agreed to support Android, which would give Google a base to compete with Symbian, the dominant portable platform, Microsoft’s Windows Mobile, the iPhone and others.

One platform not often mentioned is Palm. The company that produced the first commercially successful PDA and now sells the Treo line of mobile phones has been struggling for years. Arguably, Palm has been more successful as a platform than as a company. There are more than 20,000 applications available for Palm devices, from products to read and edit Microsoft documents, to restaurant guides, to games, to bedside software for physicians. Yet, Palm has steadily given ground in market share and found it difficult to make a profit. The company has also waffled on its commitment to its own operating system, selling devices built on Windows Mobile as well. In the last quarter, Palm reported a loss of $31.5 million on revenue of $312 million.

Palm’s troubles can be trace to a failure to come up with a “hot” device after the initial success of the Treo, much as Motorola stumbled after the success of its Razr. The company has consistently lagged in providing the features that other phones offer, such as Wi-Fi. In a hit-driven world, the platform becomes important for holding on to fickle customers. If you have your favorite games or Zagat restaurant guide on one platform, this may discourage you from moving to another just to own the next fashionable phone.

But as Palm’s failures show, you also have to make great phones that people want to buy, which is where Apple still retains the advantage. Everybody else is still running to catch up and be cool. Even the new BlackBerry Bold introduced today (see photo) looks a lot like what an iPhone with a real keyboard might look like. For now slim and trim remains the holy grail.