Today I went running with the apple watch. I used the activity app and thought it was a good experience. I went this morning for 35 minutes. I found that the activity app reads my heartbeat every 5 seconds when using the app and every 10 minutes normally. After the run, my battery life was 93 percent on my watch (I have the screen brightness set on medium). I was impressed with the app. I have always used the Nike+GPS app. I will give that one a try on Monday and compare the two.