The International Data Corporation (IDC) on Thursday published a report detailing how it expects the wearable market to take shape through 2019.
According to IDC, the wearable market—which includes fitness trackers and smartwatches—will pass 111.1 million shipped devices in 2016, up from 80 million units shipped in 2015.
By 2019, IDC expects that number to nearly double, with vendors shipping some 214 million wearable devices.
Senior research analyst for mobile device trackers at IDC Jitesh Ubrani noted that wearables of the future will come in different form factors, saying “[s]marter clothing, eyewear, and even hearables (ear-worn devices) are all in their early stages of mass adoption.” He continued, “Though at present these may not be significantly smarter than their analog counterparts, the next generation of wearables are on track to offer vastly improved experiences and perhaps even augment human abilities.”
The report then turns its attention to smartwatches, the wrist-worn gadgets that double as an activity tracker and notification system on a user’s wrist. Ramon Llamas, research manager for IDC’s wearables team, echoes sentiments expressed by AT&T Mobility (T) CEO Glen Lurie about the future of smartwatches.
“The smartwatch we have today will look nothing like the smartwatch we will see in the future,” Llamas said. He continued, “Cellular connectivity, health sensors, not to mention the explosive third-party application market all stand to change the game and will raise both the appeal and value of the market going forward.”
And leading the way will be the Apple Watch.
IDC estimates Apple’s (AAPL) smartwatch market share in 2015 at 61.3%, followed by Google’s (GOOG) Android Wear platform at 15.2%, with Pebble coming in third at 8.6%. Shipment estimates are 13 million, 3.2 million, and 1.8 million, respectively.
Over the next three years, IDC expects Apple to hold on to the top spot. In 2019, the firm expects Apple to ship 45.2 million Apple Watches, with Android Wear reaching 34.3 million, and Samsung’s Tizen smartwatch line reaching 2.5 million devices. Those shipment numbers translate to a market share of 51.1%, 38.8%, and 2.8% respectively.
Smartwatch maker Pebble is expected to ship 2.3 million devices in 2019, with 2.6% market share. It’s an increase of half a million devices shipped when compared to 2015. Though, it will see a 6% decrease of its market share over the four-year time period. On Tuesday, Pebble updated its lineup with native step counting and sleep tracking support—a feature the company’s lineup had long lacked.
Make sure to sign up for Data Sheet, Fortune’s daily newsletter about the business of technology.
For more about the Apple Watch, watch this Fortune video: