HI Sai
please make sure yoy have carefully read and completed all of the configuration for the app.
Make sure you have searched for SAP Notes for My Accounts & My Contacts and applied those relevant to your environment.
Only accounts and contacts assigned to you will be shown. If no accounts are shown it may be that there are no accounts assigned to you.
My Contacts shows contacts of your assigned accounts. So start with the My Accounts app
If you have done and checked all that and still can't get it to work raise a SAP Message
Btw I have personally seen these apps working at a customer site.
Rgds
Jocelyn