Turns out developers were in pretty heavy anticipation of seeing Tim Cook take the stage at yesterday’s “Hey Siri” event, but some new features got them a little more excited than others.
A few of the developers and beta testers for a heart-monitoring Apple Watch app called Cardiogram wore their devices in workout mode during yesterday’s event and what were the results?
It seems that the Apple Pencil really had developers’ hearts racing. Outside that, the watchOS launch date and the Airstrip demo really piqued their interests. Check out some of the partial data from the event below.

Go to Cardiogram’s site for full data from their app.
I chatted with Brandon Ballinger who works at the UCSF Health eHeart Study and helped build Cardiogram for the Apple Watch.

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“Cardiogram lets you chart and analyze all that Apple Watch heart rate data sitting around in the Health app. Many of our users use it for running or cycling,” Brandon Ballinger told TechCrunch in an email.
Ballinger says that the mission of the app is to help keep people more informed about their heart health.
“We think the Apple Watch can be used to create something similar to a check engine light for your heart. Almost all of these conditions are treatable or sometimes even curable.” Ballinger said. “When you have a potentially life-threatening arrhythmia, your watch should tell you, connect you with medical care, and help you get it fixed. You shouldn’t find out about a treatable arrhythmia by coming to the emergency room with a stroke.”
Cardiogram is currently live in the App Store and will be starting a private beta for Android Wear in the near future.
