User doesn't see the applications tab
When I log in the portal with user profile the applications tab is not shown, so how can a user run an application in portal?
On the other hand if you are in administrator profile you can see the applications tab and run an application, but it is not assigned to your manager and s/he can't review it.
The Applications page is an administration page used to manage and create applications. As such, it can only be accessed by administrators.
An application is a stand alone item supposed to be accessed by the end users through its URL directly.
So you should communicate the Application URL to the users. They cannot access it directly in the portal.
If the users need to access several applications and you want them to see a page with this list of applications, then you can build a page that does just that and create an application to host it. You will then communicate this application's URL only to your end users.
I hope that helps