Just as Apple was riding its latest high, enjoying the smash-hit known as the Apple Watch, here comes Debbie Downer with a dose of bad news: that tattoo on your wrist could throw a wrench in the workings of your watch.
As CNN Money reports today, some early adopters of the Apple Watch are complaining that the device’s highly touted heart-rate sensor apparently doesn’t function when there’s an I Love Mom or cute colorful dolphin or other tat in the way.
Apple did not respond to CNN, but the report goes on to say that tattoos might also mess with your ability to pay for that cappuccino you just bought at Starbucks:
Since the Apple Watch uses your heart rate to determine whether you’re wearing it, you might not be able to use Apple Pay, receive notifications, place calls, or use certain apps if you have tattoos on your wrists.
Some Apple Watch wearers on Reddit and Twitter complained about the tattoo issue, and Apple blog iMore confirmed that the problem exists.
So what gives?
The issue stems from the way that the Apple Watch senses your heartbeat. According to Apple, the back of the Watch rapidly flashes green and infrared light at your skin, which gets absorbed or reflected by your red blood. When your heart beats, there is more blood in your wrist, and there is less blood between beats. By sensing the timing between your heartbeats, the Apple Watch can calculate your heart rate.
As it turns out, solid-colored tattoos — particularly red ones — also absorb the green light and reflect red light. Black tattoos, which absorb both green and red light, can also screw up the Apple Watch’s heart rate sensor.
apple watch tattoo
According to one user mentioned by Reddit, the tattoos and Apple Watch’s sensor didn’t quite see eye to eye. Bu there may be hope:
The Apple Watch works fine with dark-colored skin, scars and skin abrasions, which are translucent, allowing light to pass through. Tattoo ink is opaque, preventing outside light from penetrating your skin.
One Reddit user found that he could turn off the Apple Watch’s wrist detection, allowing notifications to come in. But he couldn’t use Apple Pay or receive calls without the wrist detection setting turned on.
Credit: Josh Edelson/AFP/Getty Images
