In 1998, Steve Mann invented, designed, and built the world's first Linux wristwatch, which he presented at IEEE ISSCC2000 on 7 February 2000, where he was named "the father of wearable computing". See also Linux Journal, where Mann's Linux wristwatch appeared on the cover and was the feature article of LJ Issue 75. Seiko launched the Ruputer in Japan - a wristwatch computer with a 3.6 MHz processor. It was not very successful, since instead of a touchscreen it used a joystick-like device to input characters (much like high scores in arcade games), and the small screen with a resolution at 102x64 in 4 greyscales made it hard to read large amounts of text. Outside of Japan, this watch was distributed as the Matsucom onHand PC. Despite the rather low demand, the Matsucom onHand PC was distributed until 2006, making it a smartwatch with a rather long life cycle. Ruputer and onHand PC applications are 100% compatible. This watch is sometimes considered the first smartwatch since it was the first watch to offer graphics display (albeit monochrome) and many 3rd party applications (mostly homebrew).
First, there’s now an option of an LTE-capable model allowing for always-on connectivity. This is through the use of an eSIM inside and an antenna cleverly hidden behind the display. The great news is that your Apple Watch 3 will share the same phone number as your iPhone, whereas other LTE-capable smartwatches have required you to juggle two phone numbers. You’ll need to pay for an additional smartwatch plan for the functionality, however.
Our top pick for most people is the Apple Watch Series 4 with GPS (starting at $399), which has a huge display, ultra-fast processor, Raise to Speak Siri, fall detection and a built-in electrical heart rate sensor for taking on-the-go electrocardiograms. It also runs watchOS 5, which makes the watch even more useful with automatic workout-tracking, offline podcast playback and a Walkie-Talkie voice chat feature.