[15][16] LTE-equipped models can also perform these functions over a mobile network, and can make and receive phone calls independently when the paired iPhone is not nearby or is powered off.

[21] That December, The New York Times reported that Apple was exploring various ideas, including a "curved-glass iPod that would wrap around the wrist", which users would interact with through the Siri voice assistant, and which "could relay information back to the iPhone".

[22] In February 2013, the NYT and The Wall Street Journal again confirmed that Apple was working on a smartwatch with a curved display,[23] and Bloomberg News said the team had grown to about 100 designers.

[24] In March 2013, Apple hired ex-Adobe chief technology officer Kevin Lynch, reporting to Bob Mansfield,[25] to lead the watch project, which would become the company's first major new product without input from late co-founder Steve Jobs.

[21] Apple started the project without specific use cases in mind, not knowing what problems the watch would solve, but felt that "technology was going to move onto the body", according to Alan Dye, who was in charge of its user interface.

According to Kevin Lynch, the team felt people spent too much time on their phone, nagged by notifications, and a watch would provide "that level of engagement [...] in a way that's a little more human, a little more at the moment when you're with somebody".

[21] In April 2014, Apple CEO Tim Cook told The Wall Street Journal that the company was planning to launch new products that year, but revealed no specifics.

[34] Initially, it was not available at the Apple Store; customers could make appointments for demonstrations and fitting, but the device was not in-stock for walk-in purchases and had to be reserved and ordered online.

[54] Additional sensors integrated into the Watch include an accelerometer, gyroscope, and barometer, which are used to determine device orientation, user movement, and altitude.

It features a new linear actuator hardware from Apple called the "Taptic Engine", providing realistic haptic feedback when an alert or a notification is received, and is used for other purposes by certain apps.

The Apple Watch Series 3 features a faster processor, the dual-core S3, Bluetooth 4.2 (compared to 4.0 on older models), a built-in altimeter for measuring flights of stairs climbed, increased RAM size, and is available in a variant with LTE cellular connectivity.

The ECG system has received clearance from the United States Food and Drug Administration, a first ever for a consumer device,[79] and is supported by the American Heart Association.

[81] Digital Trends gave it a score of 5/5, calling it Apple's best product and praising the design, build quality, and software, among others, while criticizing the battery life.

[96] The S6 incorporates an updated, third generation optical heart rate sensor and also enhanced telecommunication technology, including support for ultra-wideband (UWB) via Apple's U1 chip (which is used to locate and communicate with other devices),[97] and the ability to connect to 5 GHz Wi-Fi networks.

Enhancements relative to the prior-generation Series 6 watch include a more rounded design with a case 1 mm larger than the Series 6; a display that is 70% brighter indoors and approximately 20% larger; improved durability via a crack-resistant front crystal;[100] IP6X certification for resistance to dust; 33% faster charging via improved internal electronics and an enhanced, USB-C based fast-charging cable; support for BeiDou (China's satellite navigation system); and the availability of an on-screen keyboard that can be tapped or swiped.

For legal reasons, blood oxygen monitoring is not available on Apple Watch Series 9 and Ultra 2 models sold in the United States after January 18, 2024.

[110] Most of Apple's claimed emissions reductions were driven by renewable energy requirements imposed on suppliers;[109][111] other factors include increased use of recycled materials, and a lower reliance on shipping products by plane, which is highly carbon-intensive.

[113] The carbon offsets used by Apple follow standards set by Verra,[114] the Climate, Community & Biodiversity Alliance, and the Forest Stewardship Council.

This decision was praised by Monique Goyens, director-general of EU consumer group BEUC, who also called Apple's claims "bogus" and scientifically inaccurate.

Features: Apple Watch runs watchOS, whose interface is around a home screen with circular app icons, which can be changed to a list view in the devices settings.

At WWDC 2015, Tim Cook announced watchOS 2.0; described by CNET as a "significant revamp", it included a new software development kit that allows more direct access to the device's hardware, new watch faces, the ability to reply to an e-mail, and other features.

watchOS 7.0 was announced on June 22, 2020, at the WWDC, and released on September 16, 2020; new functions include sleep tracking, additional watch faces, handwashing detection and new workouts such as dancing.

[133] Venture capitalist Marc Andreessen said he "can't wait" to try it,[134] and Steve Jobs' biographer Walter Isaacson described it as "extremely cool" and an example of future technology that is "much more embedded into our lives".

Farhad Manjoo of The New York Times mentioned the device's steep learning curve, stating it took him "three long, often confusing and frustrating days" to become accustomed to watchOS 1, but loved it thereafter.

[143] Some users have complained that the logo and text on the back of the Apple Watch Sport model, primarily the space gray version,[146] can be easily worn off.

[148] Time's Tim Bajarin summarized the breadth of reactions, writing that "there is not enough information yet to determine how this product will fare when it finally reaches the market next year".

[120] The ban is due to Apple's failure to meet a 40% quota requirement for local component certification implemented by the Indonesian government, according to minister of industry Agus Gumiwang Kartasasmita.

[161] In October 2023, the United States International Trade Commission (ITC) ruled that Apple Watch products infringed upon patents for light-based pulse oximetry that are owned by medical technology company Masimo.

This ruling would allow the ITC to impose an import ban, provided it is not overruled by presidential veto power within a 60-day review period ending December 25.

[165] Blood oxygen monitoring is not available on Apple Watch Series 9 and Ultra 2 models sold in the United States after January 18, 2024, designated by part numbers ending in "LW/A".