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.
Linker - Cloud based bookmark manager
Siimpl Bookmarking - Start collecting and organizing what interests you
Sum It Up - A micro bookmarker & multicolor highlighter for note keeping
BrainyTab - Bookmark manager that makes you smart(er)