Apple has reacted officially to the Tattoogate scandal concerning its Watch wearable device, admitting that in some circumstances the watch will fail to take an accurate reading.
The firm has not publicly commented on the tattoo problem, but new information on its support pages tackles the complaints that some users have raised.
Apple said in a section about the forces that might affect the Apple Watch sensors that "many factors" can affect performance. These include blood flow, motion and body temperature.
"Many factors can affect the performance of the Apple Watch heart rate sensor. Permanent or temporary changes to your skin, such as some tattoos, can also impact heart rate sensor performance," the company said.
"The ink, pattern and saturation of some tattoos can block light from the sensor, making it difficult to get reliable readings."
Apple has recommended a workaround that involves using the device in a different way. "If you're not able to get a consistent reading because of any of these factors, you can connect your Apple Watch wirelessly to external heart rate monitors such as Bluetooth chest straps," the firm said.
The Apple Watch came in for early criticism from several buyers who claimed that it does not function properly on tattooed skin.
Reddit users complained that wearing the watch on a tattooed area prevents unlocking and affects the collection of health results and information.
"The watch would lock up every time the screen went dark and prompted me for my password," wrote Reddit user Guinne55fan.
"I wouldn't receive notifications. I couldn't figure out why especially since the watch was definitely not losing contact with my skin. Also I couldn't find anything online with people experiencing this issue.
"I was about to give up and call Apple when I decided to try holding it against my hand (my left arm is sleeved and where I wear my watch is tattooed as well) and it worked.
"My hand isn't tattooed and the Watch stayed unlocked. Once I put it back on the area that is tattooed with black ink the watch would automatically lock again."
Guinne55fan added that the problems extend into notification alerts. The alerts do not come through when the watch is on the tattooed area, but moving the watch to a clear skin area restores the system.
Apple has offered some assistance, and additional advice is due this week, according to the Reddit post.
Apple has released information about what kind of apps will be approved for the Apple Watch.
One notable example that will not be approved by Apple is anything that tells the time. "Watch apps whose primary function is telling time will be rejected," said Apple.
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