I have just updated my Windows Store Flickr app adding support for HTTPS. In June Flickr will switch to only using HTTPS for 3rd party apps so any apps using plain http will no longer work. So I have updated all the API calls to use secure HTTP and the app will continue working in June. There are no other new features in this build, I will look at new features with the next release.
With the app you can upload a single file or multiple photos to Flickr and view your collection of Flickr photos. It will also generate HTML code for embedding photos in to a website or blog and you can share photos via email or DLNA using Play To.
The app is free from the Windows Store.