Koken.me is described as 'Koken is a free web site publishing system developed for photographers, designers, artists and creative DIYs. It allows publishers to manage, edit and publish personal web sites of their work' and is an app in the development category. There are more than 10 alternatives to Koken.me for a variety of platforms, including Self-Hosted, Web-based, Mac, Windows and Linux apps. The best Koken.me alternative is PhotoPrism, which is both free and Open Source. Other great apps like Koken.me are Piwigo, MediaGoblin, Lychee and Slidebox.
ResourceSpace is an open source Digital Asset Management system originally developed for Oxfam by UK company Montala Limited in 2006. Montala continue to manage the project in addition to providing commercial hosting, support and development services relating to the software.
Recall is an open-source and decentralized alternative to Google Photos built on top of Blockstack. Photos are stored encrypted with the user's private key and therefore not accessible to anyone else.
JCDSee Web Photo Gallery is a separate project from the desktop Java client. It is a web-based photo viewing / cataloging system written in Perl.
DragNDropz is a centralized online image gallery software platform that can stand alone or be used with existing websites. DragNDropz allows you to create and share unlimited image galleries using a simple drag and drop interface.
Razuna is an open source Digital Asset Management system. It features version management, collaboration, powerful search, and secure storage and retrieval. NB: Razuna requires a server with Tomcat / Java support; i.e. probably won't work on most shared web hosting accounts.
United Kingdom
Zoph (Zoph Organizes Photos) is a web based digital image presentation and management system. In other words, a photo album. It is built with PHP, MySQL and Perl.
