Zencoder
Zencoder is the creator of an open-source HTML5 video player, Video.js, built with Javascript, HTML, and CSS. Video.js plays video via native playback in all HTML5 browsers and devices, or through Adobe Flash when HTML5 playback is not available.
Internet Browser (Nintendo 3DS)
On the New 3DS, a new video player is integrated into the browser. It can play back both 2D and 3D Videos on webpages which supports HTML5. This eliminates the need for the dedicated YouTube app on the new 3DS.