Hacking Glass

So I got my hands on another Glass device and can now play with it a bit longer.

Disclaimer: Rooting and flashing your device voids your warranty and can brick your Glass. Also you won’t receive OTA updates afterwards. This is not an instruction manual. I just use it as a scratch pad to give a record what I did and what worked for me. The commands below will erase all data on your device. Proceed at your own risk.

Rooting and Flashing Images

To get root follow the instructions from Google. Unfortunately, the fastboot under Mac OS does not work. I could use a virtual machine on my Mac with ubuntu to get root and flash images.

adb devices
adb reboot-bootloader
fastboot devices

fastboot oem unlock

I needed to execute the last command twice. The first time it just asked me if I was sure if I want to void my warranty etc.

Next I flashed the boot image from the Glass developer page.

fastboot flash boot boot.img
fastboot reboot
adb root
adb shell

If you want to update to a new OTA (in my case XE12) and rooted your device, you can download the zip with all necessary images from Google. It’s cool that they support rooting and flashing (even if it voids your warranty).

fastboot flash boot boot.img
fastboot flash system system.img
fastboot flash recovery recovery.img
fastboot flash userdata userdata.img
fastboot erase cache

Reading out the Proximity Sensor

I’m most interested in accessing the proximity sensor facing the eye. So thanks to Philip Scholl’s and Shoya’s help, I was able to do it. The device is under

adb root
adb shell
> cat /sys/bus/i2c/devices/4-0035/proxraw

Gives back one raw proximity value from the sensor. Unfortunately without timestamp. If you want to read out the proximity data from Android Apps etc. you need to change the access rights.

>chmod 664 /sys/bus/i2c/devices/4-0035/proxraw

Privacy Enhancement

As I will be visiting the Chaos Communication Congress next weekend, I wanted to “privacy enhance” GLASS for the event. I want to wear Glass but don’t really need the camera functionality.

So I used my 3Doodler to make a simple attachment to block the camera of.


The tricky part is that the light sensor for adjusting screen brightness is directly under the camera. If it’s blocked the screen will be very dark. Here’s the “privacy enhanced” Google Glass version.

Glass Enhanced

and a picture taken by it. It’s not completely black due to the issue with the light sensor, yet I think it’s a start ;)

Glass Enhanced

Here is the very basic stencil I used to build the attachment.