Ah, the sweet rejuvenation of a good night's sleep is like nothing else. The trick is actually getting a solid eight hours of rest. It is an important part of health and well being, and unfortunately, sleep tracking is not a native feature of Apple's smartwatch. That is going to change, though, with Apple said to be testing a built-in sleep monitor.
There are third-party apps that offer this functionality on the Apple Watch, though there are shortcomings with some of them. Sleep tracking is also a competitive advantage that Fitbit holds over Apple, as the company's fitness bands can automatically detect sleep stages—light sleep, deep sleep, and that all-important REM sleep.
How long that advantage lasts remains to be seen. Citing people who are familiar with Apple's work, Bloomberg says the company has been testing its sleep-tracking feature for the Apple Watch for several months. Supposedly these tests are being conducted at secret sites around its headquarters in Cupertino, California.
This is a feature that could be added to the Apple Watch by 2020, which presumably means two more generations from now (the latest generation Apple Watch is the Series 4 which added a built-in ECG and fall detection).
Not to be taken lightly, the smartwatch market is rapidly growing, and it is dominated by Apple at the moment. According to research firm NPD Group, smartwatch sales ballooned 51 percent year-over-year to $5 billion in the US last November. And although it didn't provide a detailed breakdown of unit sales by manufacturer, it said the Apple Watch was the "clear market leader" during the 12-month period.
This is happening as Apple is seeing a slowdown in iPhone sales. So, it is reasonable to assume we are going to see Apple put a priority on expanding its Apple Watch's capabilities, presumably starting with sleep tracking.