The heart rate monitoring features of the Apple Watch got a shout-out at yesterday’s event: the new watch will monitor more heartbeat-related metrics and Apple will partner with AmWell and Stanford for a medical study. But at the same time, heart rate app Cardiogram was quietly tracking how users reacted to the day’s announcements.


Users opted in to this project, so nobody’s heart rate was observed without their permission. Here are the top five moments, as told by users’ averaged heart rates:

1:20pm , as Apple was preparing to announce the new Apple Watch. (76.1 beats per minute)

, as Apple was preparing to announce the new Apple Watch. (76.1 beats per minute) 1:27pm , the announcement of the Apple Heart Study. (75.8 bpm)

, the announcement of the Apple Heart Study. (75.8 bpm) 1:33pm , when Dierdre Caldbeck took a phone call on her Apple Watch while paddleboarding. (76.3)

, when Dierdre Caldbeck took a phone call on her Apple Watch while paddleboarding. (76.3) 1:42pm , the announcement of the Apple TV 4K. This was the highest average heart rate of the presentation. (78.1)

, the announcement of the Apple TV 4K. This was the highest average heart rate of the presentation. (78.1) 2:25pm, when FaceID was announced (77.4 bpm), followed by a drop to the lowest heart rate of the session a little while later when the iPhone X’s price was revealed as $999.


This was not a super rigorous scientific study, and Cardiogram says it only included 63 people. So don’t read too much into the results; you still get to decide for yourself which parts were the most thrilling.

If you want to check out the heart-pounding moments yourself, be aware that the official livestream is off by about three minutes; the timestamps here correspond to what livebloggers like our friends at Gizmodo reported.