The most unique feature in the 2023 Apple Watch Ultra 2 and Apple Watch Series 9 is the Double tap gesture. It allows users to control their smartwatches with just one hand and without touching the screen.
When enabled, users need to tap the index finger and thumb of their watch hand to answer or end calls, take photos, start or stop timers, open Smart Stack, and more. Double tap gesture feature was recently released on compatible smartwatch models in the watchOS 10.1 update.
Although it resembles the functionality of the Assistive Touch Accessibility feature available in Apple Watch Series 5 and later models, the Double tap gesture is not the same.
Double tap gesture seems like a software limitation, not hardware
Apple claims that the feature is more power-intensive and responsive because it is enabled by the new 4-core Neural Engine in S9 Sip with the ability to process data 2x faster with a new machine learning algorithm than the previous Apple Watch Series 8 and Ultra 1.
However, a teardown of Apple Watch Ultra 2 and Series 9 by iFixit revealed that Apple has not used a new sensor in both smartwatches for the Double tap gesture. It seems like a software limitation by Apple to not expand the feature on older models. Let me explain.
Double tap gesture might release on Apple Watch Series 8 and older, like Assistive Touch
In 2021, Apple introduced a new Accessibility feature, Assistive Touch for users with upper body limb differences to control their Apple Watch without having to touch the display and using hand gestures like clenching or pinching to answer incoming calls, access the Notification Center and Control Center, and more.
Although at the time of launch, Assistive Touch was only available on Apple Watch Series 6, Apple Watch SE, and Apple Watch Series 7, it was later expanded to Apple Watch Series 5 and older models compatible with the watchOS 8.3 update.
We are hoping that the company does the same with the Double tap gesture because, like Assistive Touch, the feature is powered by on-device machine learning to process data from the gyroscope, accelerometer, and optical heart rate sensors available on Series 4 and newer models.
Apple describing Double tap gesture in 2023:
The new double tap gesture is enabled by the faster Neural Engine in Apple Watch Ultra 2, which processes data from the accelerometer, gyroscope, and optical heart sensor with a new machine learning algorithm. The algorithm detects the unique signature of tiny wrist movements and changes in blood flow when the index finger and thumb perform a double tap.
Apple describing Assistive Touch in 2021:
Using built-in motion sensors like the gyroscope and accelerometer, along with the optical heart rate sensor and on-device machine learning, Apple Watch can detect subtle differences in muscle movement and tendon activity, which lets users navigate a cursor on the display through a series of hand gestures, like a pinch or a clench.