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View Khan Academy's library of over 4,000 educational videos.Viewer for Khan Academy makes it easy to view Khan Academy's library of over 4,00 …

Pensive takes a simple approach to RSS feeds. We've focused every aspect of the experience to let you easily add, organize, and read your feeds. A …

Badgr puts the power of badges in your pocket. It lets you store and display badges you've earned from any badge issuer, and it helps you discover …

Developed in partnership with NASA, Astronomy Picture of the Day (APOD) brings the vastness of space right into your hand. Browse through decades of h …