I am building an app that should 'sync' up email messages arriving at an Exchange server 2010. In order to do this I would like to automatically forward all the email messages, based on a list of employees, that are coming into the Exchange server to my app, which has an own generic email address. Is this possible to do so with Exchange Server 2010 ?
Yes, Exchange has a reasonably powerful mail redirecting function called 'transport rules'.
There is an easy to use GUI that controlls this within the Exchange Management Console under:
-Microsoft Exchange On-premises, -Organisation Configuration, -Hub Transport, -Transport Rules
Then select 'New Transport Rule...' in the Actions pane and follow the GUI
Transport rules can also be created via powershell commands in the Exchange Management Shell
http://technet.microsoft.com/en-gb/library/bb124737(v=exchg.141).aspx