An estimated 8.4 billion connected things were in use worldwide in 2017, up 31% percent from 2016, and will reach 20.4 billion by 2020, according to Gartner, Inc., Stamford, Conn. In fact, total spending on endpoints and services reached almost $2 trillion in 2017. 

Regionally, Greater China, North America and Western Europe are driving the use of connected things and together represent 67% of the overall Internet of Things (IoT) installed base in 2017.

The consumer segment is the largest user of connected things with 5.2 billion units in 2017, which represents 63% of the overall number of applications in use.

From 2018 onwards, cross-industry devices, such as those targeted at smart buildings, including LED lighting, HVAC and physical security systems, will take the lead, as connectivity is driven into higher-volume, lower-cost devices. In 2020, cross-industry devices will reach 4.4 billion units, while vertical-specific devices will amount to 3.2 billion units.

While consumers purchase more devices, businesses spend more. In terms of hardware spending, in 2017, the use of connected things among businesses will drive $964 billion. By 2020, hardware spending from both segments will reach almost $3 trillion.

"IoT services are central to the rise in IoT devices," says Denise Rueb, research director. "Services are dominated by the professional IoT-operational technology category in which providers assist businesses in designing, implementing and operating IoT systems. However, connectivity services and consumer services will grow at a faster pace. Consumer IoT services are newer and growing off a small base. Similarly, connectivity services are growing robustly as costs drop and new applications emerge."