For true tablet mirroring to your TV, with audio and video , you will require an on board HDMI port on your tablet, like the one on the more expensive Nexus 10. As dominic and StewMc have said the Chromecast does offer the ability to view a growing list of Internet content, your Nexus 7, which acts much like a remote controller, allowing you to queue up content. The Chrome browser for the desktop supports the Cast extension, which allows the content of the browser to be sent or cast to a TV with a Chromecast device. So yes I can watch and hear Amazon Prime video content cast from my PC to my TV with the connected Chromecast device. Unfortunately at this time, the mobile version of Chrome on our Nexus 7, doesn't support the cast extension, but rumors exist, that it will in the future. Remember the $35 price tag is due to expected revenue for Google from its use, so look for the tab cast feature on our Nexus 7, once Google figures out the most advantageous venue for them. I cannot say that I blame them, but I would prefer to see tab casting sooner than later.
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