The cast feature isn't implemented yet in Chromecast. However, for streaming video I would recommend using the realplayer cloud app. You can stream any video (and audio I think) content from your phone, or anything in your realplayer library. For example if you have a computer on the same wifi that has videos in the library (not even necessarily uploaded, just in the library) you can stream it using your N5 because it will be in the app.
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