Apple unveiled a new generation of its watches, the Apple Watch Series 12 and Apple Watch Ultra 4, with a new health system that measures heart rate in the background every 5 seconds throughout the day, up to 60 times more than the previous generation. It also includes new AI-based features for understanding voices and conversations.

Apple has developed its health sensor system by increasing the area of the electrodes to improve the accuracy of electrocardiograms (ECGs). The sensors have been redesigned with larger, more efficient green LEDs to measure heart rate even during movement. It also tracks sleep, workouts, and other health indicators.

One of the most notable additions is Live Rewind, which allows users to go back to what was said in the last 15 seconds and convert it into written text. Users can ask Siri about its content or save it for later reference.

Apple has also introduced Siri Recap, an AI feature that generates summaries of daily conversations, such as work meetings, parent-teacher conferences, and automatically extracts key points from them.

The two watches can also recognize sounds such as alarm sirens, doorbells and children’s cries and send an alert to the user, even when the iPhone is not nearby, in a feature specifically targeted at the deaf and hard of hearing.

Apple confirmed that the voice intelligence features do not create or store audio recordings, and that sound processing takes place with privacy preserved, while texts and summaries stored are encrypted when synchronized via “iCloud”.