While the latest versions of the Chromecast app allowed mirroring, unfortunately the number of devices that it officially supported on initial rollout was pretty low. Fortunately, root users have a way to get most phones working with both video and audio Chromecast mirroring.
The patch has been tested to add the complete mirroring functionality to the following phones: ASUS PadFone X, ASUS PadFone 2, Nook HD+, Droid RAZR MAXX HD, Droid RAZR M, Sony Xperia Z, Sony Xperia Z Ultra, Sony Xperia Z1, Sony Xperia Z1 Compact, Sony Xperia Z2, Sony Xperia ZL, Huawei Honor 3C, HTC One M8 (Including GPE), Motorola Moto X, Motorola Moto G, Samsung Galaxy S III (as of v4), Samsung Note 8 Tab, Samsung Note 10.1 Tab, Samsung Note Pro 12.2 Tab, Samsung Galaxy Tab Pro 8.4, Samsung Galaxy Tab 4, Nexus 7 2012, Oppo Find 7, Oppo Find 7a, OnePlus One, LG GPad 8.3, LG G2 Mini, LG Optimus G, LG G Flex, NVIDIA SHIELD, Xiaomi Mi2, Sero 7 Pro.
Additionally, all the devices that are officially compatible will work too, but if it works for you there’s really no reason to play with this.
It may also work on older phones, but that may be both ROM and hardware dependant. It explicitly lists the HTC EVO 3D as not working, but who knows what was done to test that.
You’ll need to be rooted, have the latest version of the Chromecast app, and then download the MirrorEnabler app from the link below.
It doesn’t require any special permissions, although being a root app that doesn’t really mean anything. It also doesn’t install via recovery, but since it’s playing around with the /system folders and file you might want to have a nandroid of at least the /system partition handy, just in case.
I’m not near a Chromecast for the next few hours to test it out, but will be checking with the M8 and the EVO 4G LTE when I get home.
Let us know how it works for you!