For it to work with the Nexus 6, you will need to download app called Samsung Galaxy Gear. To be able to download it, you will need a Samsung device. The only other option, if you have a Gear S would be to use the Gear S as a standalone device which would not communicate with the phone. If you want to use the Nexus 6 with a wearable, you will have to get an Android Wear device.