The Apple Watch is not just a niche smartwatch anymore. In fact, Apple claims it's the most popular watch — smart or otherwise — in the world. The Series 4 is the latest generation of this product line, and it adds several features that sound great on paper. This includes the ability to take ECG readings, fall detection, larger and better displays that go all the way to the edge, and an improved heart rate sensor. It also has a GPS to track your runs accurately, and can be worn while swimming to track your swims as well. But is it really worth the hefty price tag it carries? We find out in our review.