Bookmark OS - Bookmark OS is like Mac or Windows optimized for bookmarks.
Raindrop.io - All your articles, photos, video & content from web & apps in one place.
Siimpl Bookmarking - Start collecting and organizing what interests you
Linker - Cloud based bookmark manager
Sum It Up - A micro bookmarker & multicolor highlighter for note keeping
Superdense - No text, just icons.