Srikanth,
Standard PO approval application : GBAPP service
My Inbox : TASKPROCESSING V2.
if you are already using standard po app, no need to use my inbox app, as the po app has lot many features and details like header and item level. The data which you see in the app is coming from the gateway gbapp service, There is a different UI as well as Gw addon involved for this application. Same is not possible in my inbox app as a default. I dont see any value addition for a user who has access to both the application.
If customer is using only my inbox app, and he wants all the po, pr, pc items in his inbox. Then he can look for following features in order to get the feel of the app to the fullest.
1. Use open task feature (Open release PO tcode from the app, eg me29n)
2. Try to use app to app navigation.Navigate to approve po app from your my inbox app. From the PO task, you should be able to navigate to approve po app, in one click.( No configs available right now with me)
3. Enhance the my inbox app in order to get the real feel of approve po app. Check out note to get the my inbox cookbook (extend task processing service to achieve header and item level data and extend UI to add more screens S2, S3 etc)
4. Approver sometimes need not go into complete details. Only the high level information should be on screen, in order to approve a po. This can be achieved by using badi implementation. Please check Fiori cloud edition to have a feel of the myinbox app. SAP Fiori, Demo Cloud Edition
steps :How to display application data in SAP Fiori Approve Requests app
Regards,
Tejas