Bookmark OS - Bookmark OS is like Mac or Windows optimized for bookmarks.
ProjectHuddle - Get design feedback and client approval using WordPress.
Squash Reports - Keep your team in touch every day
Invision - Prototyping and collaboration for design teams
BugFeedr - Easily collect product feedback from your users.
Savahapp - The all-in-one design sharing, collaboration, workflow and app prototyping platform