Ambiq is market leader in lowest power MCU / SOC in the industry, with their Apollo family they provide a nice range of extreme low power products, to control the whole application like a watch or any other wearable. With the powerful ARM cortex M4F, optional an Apollo could have a “blue” version which is a connectivity for Bluetooth LE.
Raltron Electronics is used for the frequency control products, the oscillator to run the MCU. Read more