This application needs Flickr API key. The APIs of flickr might need an API key to be created. I request the you to sign up for a free account at https://www.flickr.com/services/api/misc.api_keys.html and use the free account only.
After the API key is generated, get this project, navigate to ViewModels folder. Open PhotoFeedViewPageModel and paste/assign the value to API string in the Fields region.
Flickr Desktop is a MVVM based WPF windows application. A user can perform search operation. Can click on an image to perform zoom in and zoom out operations. A user can also navigate through the pages if there are multiple pages.