[Philips, Sony, TCL Android TV] nyteryder79:
I've had my XBR55X850C for about a week now and thought I'd share some tips/info.

Updating the TV

First thing you should do is update your TV. There were 2 types of updates available for me and I believe I did these in the wrong order and this caused my Netflix app to disappear (instructions to fix this down below). There was a Sony update and there was an Android update. I installed the Android update first, then the Sony update (which took forever). I think I should have done this in the opposite order and would have probably only needed the Sony update. To install the Sony update, you will see an app with a green icon called "Sony Select". Choose this and you should be prompted with a message saying that an update is required. Follow these steps to update your TV (takes about an hour). Once this is done, check in Settings to see if there is also an Android update available and install that as well. Once that is done, below are some tips I'm providing based on my user experience to get the most out of your TV.

Playing Video Files Over Your Local Network

I'm a cord-cutter and as such I watch files off my network frequently. I don't prefer using DNLA servers like Plex because there's really no need to have everything transcoded from your media server to your Android TV device since my Android TV has enough processing power to handle playing my video files over my network. The simple solution here was to go to the Play Store using my browser from my computer and install ES File Explorer and MX Player Pro to my Sony Bravia. Now I can browse my local network with ES File Explorer, find the video I want to watch and open the video with MX Player Pro.

MX Player [Pro]

Regarding MX Player, one big tip I can give you is to make sure you have the codecs installed for proper audio output. Got mine here: http://xdaforums.com/apps/mx-player/mx-player-custom-codec-dts-support-t2156254

Another helpful MX Player Pro tip is to use HW+ for video and SW for audio. Using HW+ for audio causes laggy, out-of-sync audio and anything other than HW+ for video causes stuttering, at least with this TV it does. Fortunately in MX Player settings, you can set HW+ default for video and SW default for audio. So far this combination works flawlessly for MKV, MP4, AVI, etc.

Installing APKs

Once you have ES File Explorer installed, you can also browse a network share and install APKs directly from the network share. Works great!

Fixing Missing Netflix App After Update

If after updating everything, you lose your Netflix app like I did, the solution was simple, but requires ES File Explorer to be installed. Using ES File Explorer, I navigated to /system/app/ and launched the netflix-ninja-release.apk file to reinstall Netflix.

Restarting Android / ADB

Occasionally I felt the need to restart Android to resolve some issues I encountered from messing around with things. However, the only "official" way to do this is to unplug my TV which seems a bit archaic. Currently, without root, the only other way I've found was to enable developer options and use ADB wirelessly to reboot Android. To do this, just like on your Android phone, tap on the build number repeatedly until it says developer options unlocked. Then I had to restart my TV by unplugging for 10 seconds and plugging back in to get the Developer Options to show up in Settings. In there I enabled the ADB features.

Next you connect to your TV using ADB wirelessly by issuing the following command: adb connect {ip of your tv}

Then you can restart the TV by issuing: adb reboot

You can ADB into your TV using a terminal app from your Android phone as well, so a computer is not necessary.

EDIT: Just discovered that I can restart Android on my TV by pressing and holding the power button on the remote control for about 10 seconds. Don't need ADB any more.

Control PS4 (or PS3 Slim) with Your TV Remote

Lastly, you can set up Bravia Sync with your PS4 (and/or PS3 Slim, PS3 Phat doesn't have HDMI-CEC) to control the UI of your console using your TV remote. This is very nice for Blu-Ray playback. Just hook up your console to an HDMI port and turn it on. Next, on your TV go to Settings -> External Inputs -> Bravia Sync Settings. Turn on Bravia Sync Control. Next, go to "Bravia Sync device list". You should see your devices listed. Press the "Enable" button. That's it. Now when you select the input for your PS4 (and/or PS3 Slim), it will automatically turn your console on and the console can be controlled using your TV remote. It also works the other way around. You can press the Playstation button on your controller and this will turn the TV on and automatically switch it to the correct input for the console.

Just thought I'd share some helpful tips and save someone else some time in getting the most out of this awesome TV. Hope this helps others out there.