Using this voice - controlled flashlight for Google Glass is a breeze. First, make sure your Google Glass has XE16+ firmware. You can do an over - the - air upgrade to get it. Once that's done, install the XE16 - compatible APK program. After installation, whenever you need the flashlight, just say 'OK Glass Toggle Flashlight' and it will turn on or off. As for maintenance, keep your Glass and the flashlight clean. Avoid exposing it to extreme temperatures or getting it wet. There's no need to root or jailbreak your Glass, so don't attempt any unauthorized modifications. If you have any questions during installation or use, refer to our step - by - step tutorial for more details.