The Apple Watch Series 4 is one of the best smartwatches around, and for good reasons. Although it wasn’t a radical departure from its predecessors in terms of design, it introduced a sleeker profile combined with a considerably larger display. But aside from this, its biggest stand-out feature is arguably the built-in ECG (electrocardiogram) monitor. Its been making headlines, and though its currently available only in the US, it is hands-down one of the most prospective new features that the Series 4 introduced. It is important not only for Apple, but for the wearables industry as a whole, as personal health monitoring devices prove time and time again to be literal life-savers.