Apple Watch: Tattoos said to prevent it working properly

Matt Warman tests out the Apple Watch 

The new Apple Watch may not work for owners who have a tattoo, It is thought that the ink may affect sensors, causing the watch's heart rate monitor to lose connection. The watch then shuts down thinking it is no longer in contact with the skin. Tests suggested that tattoos in dark and solid colours interfered with the device most.

Users of the watch, which went on sale last week, took to social media under the hashtag #tattoogate to air their frustration.

One anonymous user on Reddit, said the device's locking mechanism, which should disengage when the watch detects it is being worn, failed to work on decorated skin.

"My hand isn't tattooed and the Watch stayed unlocked," he said.

"Once I put it back on the area that is tattooed with black ink, the watch would automatically lock again."
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It has also been claimed that the watch does not deliver the soft pings that alert a user to incoming messages if over a tattoo.
The heart rate readings were also significantly different on the tattooed and untattooed wrists.
The watch is said to use green LED lights paired with light-sensitive photodiodes to detect the amount of blood flowing through the wrist and calculate the frequency of heart beats.
A website support page from Apple says tattoos can interfere with readings from the heart rate monitor, but does not mention interference with other functions.
"Permanent or temporary changes to your skin, such as some tattoos, can also impact heart rate sensor performance. The ink, pattern, and saturation of some tattoos can block light from the sensor, making it difficult to get reliable readings," it says.
Apple has so far declined to comment.