According to The Daily Telegraph, an SEC filing by UK health tech startup Rockley Photonics reveals that Apple has been its largest customer over the last two years, and it has an ongoing “supply and development agreement” with Cupertino. Rockley develops sensors able to detect various blood levels, including glucose, by firing infrared light through the skin.
The filing lends credence to reports from January that claimed Apple and Samsung are working on non-invasive blood glucose monitoring for their respective wearables. Conditions such as type 1 diabetes, which affects this writer, require checking blood glucose levels many times every day.