1) The open hardware movement has exploded since 2012 due to factors like affordable 3D printing, single board computers like Arduino and Raspberry Pi, and crowdfunding platforms like Kickstarter.
2) Makers can now easily design prototypes, produce circuit boards and casings, and fund production for their hardware projects using these open hardware tools and communities.
3) Communication standards like Bluetooth Low Energy have also helped by providing inexpensive, standardized connectivity for Internet of Things devices.