Exchange of information between two Web Applications [closed]

Answer 1

you can use a huge amount of solutions

1. web services on both applications, the first one which will receive data for a generating the report(App2) and the second one which will receive the report on app1 side
2. file based solution where the first application will place the data which should be processed by App2, App2 reads this data, and after processing the application 2 will place the result of the report generating to a filesystem
3. etc.

The selection of approach depends on your goals/times/resources/architecture of existing applications and many other conditions which might have influence.

Read about

http://en.wikipedia.org/wiki/Enterprise_application_integration

http://en.wikipedia.org/wiki/Enterprise_Integration_Patterns