Affiliate Disclosure
If you buy through our links, we may get a commission. Read our ethics policy.

Apple Watch wrist detection failing with some tattoos, users complain

Image Credit: Reddit user guinne55fan

Last updated

Wrist detection on the Apple Watch may not work properly for some people with lower-arm tattoos, as they appear to fool the device's sensors, some early adopters of the device have said.

One owner noted in a Reddit post on Monday that when he wore his Watch on a wrist tattooed with black ink, he couldn't receive any notifications, and the device would lock every time it went dark. Before trying to contact Apple, though, he tested the Watch against his unmarked hand, which suddenly allowed it to work as intended.

Turning off wrist detection entirely was said to solve the problem, but at the expense of features like Apple Pay.

Wrist detection relies on light sensors on the back of the device which also serve as a heart rate tracker through a method known as photoplethysmography. By flashing infrared and/or green LED lights, the Watch can detect blood flow. Dark skin color could theoretically affect accuracy, although Apple states that the Watch will increase LED brightness and sampling rate to deal with tough reads.

The issue could be down to the materials that tattoo ink is made from. Many pigment bases are derived from heavy metals, like mercury, copper, or nickel, which may interfere with the sensors.



214 Comments

thewhitefalcon 4444 comments · 10 Years

Solution: Stop treating your body like a billboard.

 

I'm sure Apple tested for skin tone, but the chemicals in the ink may be throwing things off.

richl 2211 comments · 17 Years

This is why having a diverse workforce is a good idea. 

suddenly newton 13819 comments · 14 Years

Of course the right thing to do is contact reddit before contacting the manufacturer of the thing you bought. /s

thrang 1037 comments · 17 Years

I know it's not the point of this article, and I understand it's a personal choice, but why do people mark their body so severely? There's almost nothing in life that is permanent, from relationships to interests to style, yet people permanently mark their body with some statement, which, of course, often diminishes in importance, and thus a new tattoo is required...repeat...repeat...repeat... Eventually you are left with an ugly pastiche of your past, some or much or which no longer holds the precious importance you believed when you got inked.