Humans have been putting technology on their wrists for a long time — and not just to tell the time. The Apple Watch and others are just the latest in a long line of wrist-borne devices, so here's a brief history of "watches" that were smart for their time too.
An AK-39, a German pilot and navigator's wrist compass, from World War II.
The Steineck ABC wrist watch cam, which was used by German spies in the late 1940s and early 1950s.
Picture: International Spy Museum//Cristina Arias/Cover/Getty Images
Dick Tracy wrist radios from 1947-1990.
An invention by Fritz Harbach: a contact plate worn like a wrist watch gives an electric shock to any attacker, 1949.
1949: Cledo Brunetti, associate director of Stanford Research Institute, wearing his invention — a tiny radio broadcasting unit.
Here's an awesome spy gadget: A field strength indicator for the Telefunken PE-484 direction finder from the late 1950s, intended for tracking down clandestine radio stations.
A Panasonic R-72S Toot-a-Loop Bracelet Radio, made in Japan circa 1972.
1981: A small, battery-powered self-protection device, designed to drive off attackers with electric shock, developed by scientists from the Massachusetts Institute of Technology.
1999: The Wristphone by NTT, unveiled at the Demo99 conference in Indian Wells, California.
2000: CASIO's WMP-1V Wrist Audio Player, the world's first wrist-worn MP3 player.
Another CASIO product from 2000: The PC-UNITE BZX-20 data viewer that can store and display contacts, calendar, and PIM (Personal Information Management) data downloaded from a computer using infrared.
2000: A wrist transmitter introduced by Hyland Hills Water World in Federal Heights, Colorado. The wireless tracking system lets parents pinpoint the location of their children to within ten feet — anywhere on the park's 64 acres.
The Fossil Wrist PDA running Palm OS in 2003.
2010s: The Zypad WR1100 and WL11XX rugged wrist-worn personal computers integrate GPS, Wi-Fi, Bluetooth/Zigbee, biometric sensor, and a digital compass.
2010: TheSpecOps Systems WC2 wearable military computer system with iKey KYB-170-OEM keypad.
A Marine checks his Altimaster-2 MA2-30 altimeter during a jump exercise on February 18, 2014.
January 6, 2015: The launch of the Nixie wrist wearable quadcopter drone camera at International CES in 2015.
Here's an odd one: The "Snore stopper" wristband, which claims to help you stop snoring with a "natural Bio-feedback technique."