Users Flag Skin Reactions on Apple Watch Series 12 and Ultra 4
Some Apple Watch Series 12 and Ultra 4 users have reported burning sensations and redness beneath the sensor area. The watches take heart rate measurements every five seconds and include changes such as a larger ECG electrode surface and larger green LEDs. Apple recommends checking band fit, keeping the watch and band clean and dry, and seeing a doctor for persistent irritation; some users improved after cleaning or an adjustment period, while others returned their devices.
Reports from MacRumors forums and Reddit describe burning and red patches beneath the sensor on Apple Watch Series 12 and Ultra 4. These models check pulse every five seconds and add a bigger ECG electrode, ring-arranged photodiodes, and larger green LEDs. Similar wrist complaints have appeared since the first Apple Watch.
Apple attributes irritation to poor band fit or trapped soap and sweat. Nickel levels are said to be low and below EU limits, while adhesive-related acrylates and methacrylates are kept away from skin by design. Cleaning and fit adjustments helped some; others returned watches. Persistent redness, swelling, or itching warrants medical advice before wearing again.
The reports could affect current and prospective smartwatch users, particularly people with sensitive skin, athletes, and those wearing devices continuously for health tracking. Irritation may lead some to change bands, clean more often, pause use, or return their watches, while others may delay upgrading. If complaints persist, they could shape consumer trust in wearable health features and encourage manufacturers to prioritize skin-friendly materials, clearer fit guidance, and better support for users who experience reactions.