However, Palm said that it is still limiting access while the tools and systems are refined and improved. General availability is scheduled for some time later this year.
Michael Abbott, senior vice president of applications software and services at Palm, said at the Web 2.0 Expo that developers are an important part of the webOS ecosystem.
"Now that the SDK will be available to a broader base of developers, we think the enthusiasm for webOS will only grow and accelerate," he said.
The Mojo SDK allows developers to build core webOS functions into applications, such as linked contacts, layered calendars, multitasking and notifications, and make use of any GPS capabilities in the handset.
Also announced at the show was a forthcoming emulator known as Classic that will allow applications written for Palm's legacy Palm OS to run on webOS devices. Classic is being developed by MotionApps and is expected to be ready for purchase when Palm's Pre smartphone becomes available to US customers from Sprint, sometime in the first half of 2009.
Palm also revealed plans for cloud services around webOS. The first of these will be the Mojo Messaging Service that will enable developers to push live updates to the cloud so that all users subscribing to that information will receive notification.
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