In end-user point of view Sharepoint Apps and SharePoint Webparts are similar, they provide a way to add functionality to our sharepoint website.The difference here is in architecture point of view for development and hosting.
Sharepoint 2013 WebParts :
We can develop webparts using server object model and also using client object model.
SharePoint webparts have to be installed in the sharepoint web front-end servers.
Code will run directly in the sharepoint servers. Server might gets impacted ,if we have poor low quality code.
Sharepoint 2013 Apps :
Sharepoint apps can be developed using Client side technologies.
Apps run outside of the SharePoint environment and are simply added to SharePoint sites.
No impact on the sharepoint website because of low quality code
This content shows up if there are no widgets defined in the backend.
Briltus Services is a firm headed by a team of experienced, skilled and passionate IT professionals. We have been successful in providing "best-in-class" Services in technology, consulting, staffing and training to business and corporations, worldwide. Our vast experience in handling international business, a mature offshore development process and a well established solution delivery model makes us the best option for our clients to work with.