Espruino on your watch!

Doing some more digging

In contrast, the Magellan Echo Smart Sports Watch was designed as an open platform and can work with any application that can leverage a ruggedized smartwatch in several colors (Figure 3, right). The watch leverages the power of both a smartphone and sports-related apps. It uses Bluetooth Smart to connect a smartphone and watch, putting the power of a smartphone right on the user’s wrist. An ARM® Cortex®-M3 runs the watch while a Bluetooth chip from Nordic Semiconductor provides the communications, and ST Micro supplies the accelerometer. Echo is compatible today with the iPhone 4S, 5, 5C and 5S. Android support is coming in early 2014.
http://chipdesignmag.com/sld/blog/tag/wifi/

The 32-bit Giant Gecko MCU, based on the ARM® Cortex®-M3 core, also plays a key role in the sport watch’s energy efficiency, enabling the Echo to operate for up to 11 months on a single CR2032 coin-cell battery. The Magellan Echo design team achieved their ultra-low energy goals by optimizing the Giant Gecko MCU’s five different energy modes and leveraging the MCU’s low-energy sensor interface (LESENSE) and peripheral reflex system (PRS). These features enable energy-friendly and autonomous peripherals to handle timing and sensor control without involving the CPU.

http://www.businesswire.com/news/home/20140106005026/en/Silicon-Labs-Giant-Gecko-MCU-Enables-Echo