The Apple Watch has adorned the wrist of many celebrities as we close in on the consumer launch, and a number of high-profile figures have willfully sported variants of the higher-end Apple Watch Edition range. Some, such as Drake, Katy Perry, Pharrell Williams and J.J. Abrams, have had to settle for those currently up for pre-order, while others, such as designer Karl Lagerfeld and former rugby player Will Carling, have been treated to exclusive combinations that are not immediately available to purchase. Now, recording artist Beyoncé Knowles has got in on the act, and she has also been snapped rocking the gold link bracelet variant first demonstrated by Lagerfeld.

Apple Watch is packed to the rafters with toys, both hardware and software-related, and among them, users will get a heart rate monitor. Part and parcel of the wearable's investment in fitness and health, we're led to believe that it will provide accurate readings of a user's heart rate, and now, the company has shed some light on precisely how the technology will work.