I've always had great battery life with the watch, even after getting 2.0. However, for the last couple weeks, I'm lucky if the battery lasts 12 hours. I went into the Android Wear app and looked at battery usage and it was showing WiFi had the largest usage by far. The graph was showing shallow usage for about 6 hours and then it dropped off a cliff. This is without the face always on. I am now trying to turn the WiFi off (since I rarely use it anyway) and see if that's the culprit. However, a couple times when I've gone back into settings, the WiFi is back on automatic, so not sure if I can turn it off completely.