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Thanks for your interest, but I can't talk about future product plans.
Regarding the SDK, it's noteworthy, though, that no details about it 
are known at all. Noone can say right now what will be available to 
whom at which terms. Without that knowledge, it's - apart from the 
policy not to talk about future product plans - impossible to say 
anything about which role the SDK will play or whether it'll play a 
role at all (as nothing is known, it could just as well be a web 
widget creation tool or a set of extensions to HTML, CSS and 
JavaScript events for Mobile Safari).
Best regards, 
Felix Schwarz