[Fire Q&A, Help & Troubleshooting] DragonFire1024:
Ok A few things before I work on recovering my phone from ever lasting bootloop or lack thereof. I can confirm, without a doubt, Screen Cast ability is ACTIVE in Amazon Fire tablets. I am pretty sure the option applies to most newer models. There are a few things you can check, which I'll get to in a moment. In the coming days, or weeks (hopefully sooner rather than later) I will be writing a detailed analysis of Miracast...or what we are being or were being made to believe what Miracast is/was. I think many will be disappointed because I think most of us had a certain vision of what Miracast is, or the perception of it, when in fact it appears to be quite the opposite.

So without spilling too much beans, let me just say this: you can blame the manufacturers and or service providers of your devices and even Google itself. Because all of them have been actively covering up this technology, though not for the reasons you might suspect. The entities involved with Miracast or Wireless Display or Cast Screen (pick your name), have done a lot of work and went through an extensive amount of trouble to do everything they can to hide the feature from you and almost completely disabled it altogether. Some actually have. Ok here is proof it exists on Fire tablets.

1) /system/build.prop In the Fire 8, some of the code you find on the web to enable Wireless Display, is already part of the hardware. So if you're root, I'm not sure there is much more you can do to the build.prop to activate it, aside from a line or two and that will vary with devices.

2) XML aka your Android Source Code. Google, at least in the past, went through extensive work to cut off Wireless Display from their devices. A user (developer?) on GitHub, RC3 kensuke has gone through his own extensive work at tracking down what was 'wrong' in the Android source that stopped Wireless Display (Miracast) from functioning. He has created tools, which I believe no longer function, to go through and make the necessary corrections, but does list some files and fixes you can try, at your own risk. You can also browse the chapters on the list to the right, that will take you through the steps to activate it, assuming it was done in your Android source.

One final thing: I've tried dozens of apps and to be honest, very very few work. They try so hard, but some information in the necessary places is just too little for the displays to function. So if you've tried Casting apps or screen sharing apps, or you've downloaded the shortcuts or makeshift Miracast sinks, and couldn't get them to work, or function very poorly, the above is why. If the hardware and code don't exist on your device, those apps and what not WILL NOT WORK. 95% of these apps require root or a custom rom and rely heavily on the available code and information your devices carry. Even then, With my rooted XT907, still couldn't get it to work.

I really do hope I can get a functioning cast system for everyone. I am doing my best and I'll share more info with you in time.

There is so much more to this and so many details and screenshots I will share with you in the coming days and or weeks.