Use Flash CS5 and packager for Iphone to develop Iphone app. Use HTML5 to develop for blackberry. you can only develop flash projects for blackberry tablets.
Thanks. I don't want to make a game etc. I only want to "play" a flash movie on the iPhone and the Blackberry. Does this make a difference in your answer?
Still you need the same.
If all you want to do is "convert" and "play" Flash movies (do you mean Flash .flv videos?) on mobile devices, use "Handbrake" to convert .flv files to mp4 and play in JWPlayer. For even better compression, after using Handbrake to get the mp4, use QuickTime Pro and "export for web"...create an m4v... iproducts version of the mp4... great quality and works perfect on iPhone with the JW Player.
Here are a couple samples:
Flash .flv video with .m4v as alt content for non Flash devices:
just the JWPlayer and m4v:
Test these videos on an iPhone to see the quality.