After a number of delays and false starts, Apple rolled out its long-anticipated ECG app for the Apple Watch Series 4 on Thursday. Originally unveiled this past September, the brand new ECG app represents Apple’s effort to transform the Apple Watch into a unrivaled health monitor in the wearables space.

The ECG app, as Apple notes on its website, allows users to easily take an electrocardiogram from their wrist. As Apple further explains, the app can alert users when they show “signs of atrial fibrillation — a serious form of irregular heart rhythm — or sinus rhythm, which means your heart is beating in a normal pattern.”

Apple adds that atrial fibrillation — which itself is a type of irregular heartbeat — can result in a stroke if left untreated. Suffice it to say, the ECG app is undeniably a huge deal and represents Apple’s biggest leap into the personal health arena yet.

With the ECG app rolling out today, Jeff Williams sat down for a brief interview with TIME where he called the ECG app a huge opportunity to improve lives.

“There’s a huge opportunity to empower people with more information about their health,” Williams said. “So this is something we view as not only an opportunity, but a responsibility of ours.”

Williams also made a point of mentioning that all personal health data collected by the Apple Watch is encrypted both on the device and when backed up to an external device.

Per usual, there are some folks who think the app might do a little bit more harm than good.

The entire TIME piece is well worth checking out as it also provides us with an interesting timeline as to how Apple’s interest in transforming the Apple Watch into a health-oriented device evolved over time.

As a final note, if you have an Apple Watch Series 4 and want to take advantage of the new ECG app, Apple describes how the entire process works as follows: