Meta has filed a patent application for an AI that listens to your voice throughout the day, works out how it thinks you are feeling from the way you sound, and keeps a timestamped log of every read.

Each read gets pinned to the moment it happened: the time, your location, what you were doing, even how you were using your phone. Some versions in the filing would listen all day; others would check in only at set times.

None of these ships in a product today, and Meta has not announced one; a filing like this stakes a claim on an idea long before anyone commits to building it.