It has been confirmed by tech giant Apple that tattoos can interfere with the working of the watch. The firm wrote on the support page that temporary or permanent changes to your skin like tattoos can have an impact on the heart rate sensor performance.
The pattern, ink as well as saturation of few tattoos can obstruct light from the sensor , thus it becomes difficult to get consistent readings. In case, due to the above mentioned factors, you are not getting a reliable reading, you can wirelessly link your Apple watch to external heart rate monitors like Bluetooth chest straps.
Apple watch when worn on tattooed wrists gives incorrect heart rate results and also loses connection.
Few users have taken out their frustration on Reddit and microblogging site Twitter in connection with the ineffective performance of the device on tattooed wrists.
Apple had described how the device would measure your heart rate a few days before it was up for sale. It described a process dubbed photoplethysmography employed by the sensors. The blood reflects green light and absorbs red light. Hence, the wearable device employs green LED lights coupled with light-sensitive photodiodes that senses the quantity of blood flowing through the wrist each time.
Though, it works well with natural skin color.