5 best BibSonomy alternatives in 2021

Voomark is a video based bookmark manager. It allows you to bookmark videos online and watch them later on your browser, Apple TV, iOS or Android devices
Perma.cc is similar to wayback machine in that it preserves your bookmarks in case the website goes away.
Mybookmarks.com is a relic of the beginnings of the Internet. It was first created in 1997 and still lives on today.
Unmark is a combo bookmark manager and to-do list. It treats your bookmarks as to-do items and helps you manage them.
Bookmark It let's you create annotations on Youtube videos and sync specific Youtube video moments to any device.