Elusen DB is a free, open-source application being developed by ClayFish Technologies. It's developmental web interface can be accessed on http://elusen.clay.fish or https://clay.fish/elusen-web (secure version).
It is a one-page web-application built using AngularJS and many other free and/or open-source front-end libraries.
Disclaimer: Usage of Elusen DB and its components are governed by the GNU GPL v3.0. ClayFish Technologies do not own this piece of software. it is owned and funded by an unknown entity.