# Apple Watch Series 12 Can Tell You What You Missed in Conversations While Checking Heart Rate Every Five Seconds > Source: > Published: 2026-09-09 20:33:46+00:00 # Apple Watch Series 12 Can Tell You What You Missed in Conversations While Checking Heart Rate Every Five Seconds ## Discover how Apple's latest smartwatch combines AI technology with advanced health tracking Apple has expanded the Apple Watch beyond health tracking with the launch of the [Apple Watch Series 12](https://www.ibtimes.co.uk/apples-september-event-premium-iphones-new-gadgets-1813467), adding artificial intelligence features designed to help users recover parts of conversations they may have missed. The new Live Rewind feature can display a text snippet of the previous 15 seconds of a conversation, while [Siri Recap](https://www.ibtimes.co.uk/apple-reportedly-confirms-rare-mass-layoffs-targeting-its-struggling-vision-pro-siri-teams-1815956) can later produce a high-level summary of key points. The timing is notable because the same watch is also gaining much more frequent [health monitoring](https://www.ibtimes.co.uk/apples-airpods-built-cameras-visual-intelligence-1815011). Apple says the Series 12 can measure heart rate every five seconds throughout the day, while its new Health Sensing System measures heart rate variability (HRV) more frequently. The combination makes the watch a more continuous companion for both physical data and everyday information. The conversation features, however, raise an obvious privacy question: how can a watch help users remember what was said without effectively recording conversations? Apple says the Series 12 does not create or store audio recordings, a claim central to the company's privacy pitch for the new feature. Instead, audio is processed in a hardware-isolated Secure Exclave and immediately deleted, while Live Rewind visibly and audibly signals when it is activated. ## Live Rewind Lets Users Recover Missed Words When the new Live Rewind feature is enabled, a user can double-press the Digital Crown to see the previous 15 seconds of a conversation as a text snippet. The feature is designed for moments when someone missed a sentence, needs to clarify an unfamiliar term or simply wants to remember what was just said. Apple says users can also ask Siri about the content or save it to the Siri app for later reference. This makes the feature different from a conventional voice recorder: the watch is designed to provide a short text-based recall tool rather than a stored audio file. [Siri Recap](https://www.ibtimes.co.uk/apple-layoffs-ai-vision-pro-teams-1815625) takes the idea further. When switched on, Apple Intelligence can generate a title and key points from a conversation after it ends. The company said the feature is intended to help users remain engaged in the moment rather than constantly taking notes. ## Why Apple Is Measuring Heart Rate Every Five Seconds The Series 12 uses redesigned optical and electrical heart sensors, with larger green LEDs enabling heart-rate measurements every five seconds throughout the day. According to Apple, this passive monitoring can provide a more detailed picture of a user's physiological state and improve the accuracy of activity measurements. The company also says HRV measurements can now be taken up to 24 times more frequently. HRV is used as one indicator of stress and recovery, and the Series 12 separates recovery HRV from overall HRV to provide different views of a user's health data. Apple assessed its heart-rate accuracy in a study involving more than 1,000 participants and compared the Series 12 with leading wearable devices. The company reported that the Series 12 achieved the highest heart-rate accuracy among the devices tested. The new data also feeds into a Readiness score, which provides users with a score from 0 to 10 and recommendations such as 'Recover', 'Pace Yourself', 'Ready' or 'Go For It'. ## How Apple Is Making Privacy Part of the Pitch The ability to process conversations through the watch's microphone makes privacy central to the Series 12's new features. Apple says its Audio Intelligence tools do not create or store audio recordings. Raw audio is processed in the Secure Exclave, a hardware-isolated compartment within the S11 chip, and then immediately deleted, according to the company. Apple also says the features do not identify individual speakers. Siri Recap produces a high-level summary rather than a full transcript and is designed to exclude certain sensitive information, including financial information and government-issued identifiers. Live Rewind also produces an audible chime and displays a microphone indicator when activated, allowing people nearby to know that the feature is being used. ## The Apple Watch Series 12 Arrives Later This Month Apple Watch Series 12 is available in 42mm and 46mm sizes, with aluminium, titanium and ceramic options. However, the availability of these features could vary per region. The US starting price is $399, while UK pricing starts at £369, with pre-orders beginning 9 September and retail availability scheduled for 18 September. Neither Live Rewind nor Siri Recap will be available immediately. Apple says both features will arrive in beta later this year, meaning the conversation-recall capabilities will initially be tested before becoming broadly established. The Series 12, therefore, represents two distinct advances at once: more frequent physiological monitoring and AI-assisted awareness of the conversations and sounds happening around the wearer. © Copyright IBTimes 2026. 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