Late last year, Apple released the ECG app for Apple Watch Series 4 as part of the watchOS 5.1.2 update. Today, the company has released the ECG app along with the new Noise app from watchOS 6 Beta to the App Store.
Of course, you have to have an Apple Watch Series 4 running on watchOS 6, or an iPhone running iOS 13 to be able to download and install these apps onto your Apple Watch.
In watchOS 6, Apple introduced access to the App Store from the Apple Watch. It lets users download and install apps directly from the Watch itself over WiFi. Which makes it easier for Apple to now move apps that were until now bundled with the watchOS only to the App Store.
So far Apple has made ECG, Noise, and the Walkie-Talkie Apple Watch apps available on the App Store.