What is the most popular cross-platform mobile development kit available?
I'm a .NET/Flex web/windows developer about to make the plunge into mobile development. I was wondering what toolkit other mobile developers use to build their applications.

Is there any toolkit that works on all mobile devices, that provides a rich interface, preferably with touch capability? Ease of development would be a bonus.

What framework do you recommend? What are its advantages and limitations?
What is the most popular cross-platform mobile development kit available?
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I'm a .NET/Flex web/windows developer about to make the plunge into mobile development. I was wondering what toolkit other mobile developers use to build their applications.

Is there any toolkit that works on all mobile devices, that provides a rich interface, preferably with touch capability? Ease of development would be a bonus.

What framework do you recommend? What are its advantages and limitations?