Lance Whitney/ZDNETSometimes a cold, sore throat, or other illness can catch you by surprise. If only you could get a head’s up as to whether you’re about to come down with something. That’s where Apple’s Vitals app may be able to help.Introduced for the Apple Watch with WatchOS 11, the Vitals app uses data recorded about your heart rate, respiratory rate, wrist temperature, sleep duration, and other metrics while you’re asleep. The app will then notify you if any metric seems out of whack compared with the usual levels. You can also manually check the app on both the watch and your iPhone (or iPad) to view the data yourself.Also: The best smart rings of 2024: Expert tested and reviewedBefore you get started, make sure you’ve updated your iPhone to iOS 18 or higher and your watch to WatchOS 11 or higher. On each device, go to Settings, select General, and tap Software Update. You’ll be told that the device is up to date or prompted to download and install the latest version.How to use the Vitals appFor the Vitals measurements to work, you must be willing to wear your Apple Watch to bed. First, you’ll need to wear it for at least seven nights with a sleep schedule enabled. During that time, the Vitals app collects a typical baseline for each of the available health metrics.To compare your nightly vitals against the baseline results, you should continually wear your watch when you go to sleep. Any notifications you receive will alert you to fluctuations in your baseline and may suggest certain contributing factors, such as new medications, changes in elevation, or an upcoming illness.Also: The Apple Watch Ultra 2 is still $80 off at Best Buy for Cyber Monday (while the deal lasts)Depending on the type of band you use, wearing the watch to bed is more comfortable than you might think. The trick is to keep the watch tight enough on your wrist so that the readings will register but not so tight that it bothers you. My watch is outfitted with a sport loop that I can easily adjust through the velcro strap. I often wear it to bed and forget it’s even there. To make sure the watch has enough juice to last the night, I charge it for a couple of hours before going to sleep, and it’s good to go. More
