I spent some time poking and prodding the Amazon Fire TV Cube today and discovered a few undocumented capabilities that I figured I’d share. None of the things I found are terribly exciting or lead to anything significant at this point, but they may interest those of you who might like to tinker with the underlying Android roots of the Fire TV Cube.
Surprisingly, the Fire TV Cube supports Safe Mode. As far as I’m aware, it’s the first Fire TV model to do so, or at least the first one to have an easy way to enable the mode. Safe Mode is a system state that prevents any 3rd-party apps from launching. It’s a feature of Android that is meant to help users diagnose and fix issues that are caused by 3rd-party apps. For example, if a buggy/defective app that you installed keeps causing the device to crash or reboot, Safe Mode gives you a way to boot the device without letting the app run, so that you can uninstall it.
To boot into Safe Mode on the Fire TV Cube, disconnect the power cable, press and hold the Volume Down button on the top of the Fire TV Cube, and connect the power cable. Keep holding the Volume Down button until you see “Safe Mode” appear in the lower left corner. It should appear just after the “Fire TV” boot animation disappears. To exit Safe Mode, simply restart the Fire TV Cube by going to Settings > Device > Restart
While in Safe Mode, no 3rd-party apps will be able to launch. Only system apps that came installed on your Fire TV Cube from the factory can be launched. You can stream videos from Amazon while in Safe Mode, but not from any other streaming service or app.
I’m not entirely sure what this next capability is for or what it does exactly, so for now, I’m just going to call it “Shutdown” because that’s the best way to describe it. If anyone knows more about this, please comment below or email me.
While the Fire TV Cube is on, if you hold the action (dot) button on the top of the device for 15 seconds, the Fire TV Cube goes into a sort-of Shutdown state. The screen goes black and all activity, including ADB logcat, seems to stop. However, the device is still powered on to some extent because the mute button remains red if the mics are muted, and you can still toggle mute on and off. The device also continues to register on the USB bus if it is connected to a PC via a USB cable. In every other sense, it seems to act as if it has shutdown. Pressing the action button while in this state causes it to reboot.
The Fire TV Cube, like all other Fire TV models before it, supports Fastboot. This is an Android state/tool that lets you modify the device’s operating system if you have the correct privileges. As with all other Fire TVs, the Fire TV Cube comes with a locked bootloader that prevents you from using fastboot to modify the device.
I expected to find a button combination to hold that would cause the Fire TV Cube to enter Fastboot mode or Recovery mode, but nothing I tried worked. This was a bit surprising, since the Echo Show supports Fastboot/Recovery by holding the Mute and Volume Down button during boot. holding the same buttons on the Fire TV Cube just caused it to boot into Safe Mode. The only way I was able to enter Fastboot mode was to connect via ADB and run the command
ADB over USB
All Fire TV models support ADB connections over WiFi, but only the Fire TV 1 and Fire TV 2 officially support ADB over a USB connection. Even though it doesn’t officially support it, it is possible to make an ADB over USB connection to the Fire TV Cube. To do so, you need to enable ADB under the developer options, connect the Fire TV Cube to a computer using the Cube’s micro USB port, and then reboot the Cube. When it boots up, you’ll find that an ADB over USB connection has been established. Windows users may need to install USB drivers for this to work. Functionaly, ADB over USB seems to be identical to ADB over WiFi.
Lastly, if you connect to the Fire TV Cube via ADB and run the command