Approved App Does Not Show in the App Part Section.

Hi all,

  I have successfully add an App from the SharePoint App Store to my SharePoint Site which was developed using SharePoint 2013. The added app was successfully Approved then when I try to add that app using the App Part to a web page I cannot Find it in the App Part section. I looked in the Site Collection Features & Site Features I couldn't find the app to activate. I don't think I have done some kind of mistake. So then what else I have to do to add that App part to the web page.

 Could someone try to solve this matter?

 Thanks,

 Regards,

 Chiranthaka