Trigraphy - Photo editing app that allows you to make mosaic/abstract looking art.
PhotoTime - Automatic face sorting & keywords tagging for your photos
Dreamscope - Make and share 'deep dream' images using dozens of supplied styles or your own.
Piwigo.org - Manage your photo collection with Piwigo. Piwigo is open source photo gallery software for the web. Designed for organisations, teams and individuals.
Photomosh - Turn anything into a vaporwave
Facial Recognition by FB - Get notified if someone tries to use your photo on Facebook