First Compile one of Your application which will give u an SWF File
Load that Swf File using SWF loader in other application
One more way is Deploy both applications in One Web Server
From one application use navigatetoUrl("Here other application URL");
Swf loader is a one class ,using that class we can load swf files so first compile one class and swf file of that first Application load into the second application
SWFLoader can be used to load on Flex application within another, but you need to consider if using SWFLoader truely meets your application architecture needs, as you could run into problems. In many cases modules are better.
This Flex 4 LiveDocs page is still relevant if you are using Flex 3:
See the section entitled: "Comparing loaded applications to modules"
Basically there are issues related to security, Flex versions, etc.
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