Before the launch of Apple's new smartwatches, there were rumors that a temperature sensor would be among the new features; while these rumors turned out to be accurate, not all the new Apple Watch models have this feature. While most smartwatches have a sensor for monitoring heart rate and blood oxygen level, a temperature sensor is a less common feature.
Samsung's Galaxy Watch 5 and Galaxy Watch 5 Pro are its only smartwatches with a temperature sensor, while the new Sense 2 and its predecessor are the only Fitbit watches with a skin temperature sensor. A more affordable smartwatch with a skin temperature sensor is the TicWatch GTH Pro which sells for $99, less than half the price of the models mentioned above.
Apple announced three smartwatches at its Far Out event — the Apple Watch Series 8, the Apple Watch Ultra and the Apple Watch SE 2nd generation. However, not all three models have a temperature sensor. For anyone looking to buy an Apple Watch with support for temperature sensing, their options are limited to the Apple Watch Series 8 and the Apple Watch Ultra. This leaves the Apple Watch SE 2nd generation as the only model announced in 2022 without a temperature sensor. Older Apple Watch models do not have a temperature sensor either.
What Does The Temperature Sensor Do?
There are two temperature sensors on the Apple Watch Series 8 and Apple Watch Ultra. One is right underneath the display, while the other is placed near the sensor that comes in contact with the skin. The sensors track the body's temperature during sleep, measuring the wrist temperature every five seconds. They are also able to detect changes as small as 0.1 °C. Apple says that the data generated, which users can view on the phone, is used by the Cycle Tracking app to estimate the ovulation date.
This is possible because there is an increase in body temperature when there is a change in hormones which can be an indication of ovulation. In addition, a combination of the temperature data, heart rate and logged cycle data provide users with a detailed view of their menstrual cycle. Users will receive notifications about possible deviations in their menstrual cycle, such as if their period will be irregular or prolonged.
Apple has also made it possible for users to share the menstrual cycle data recorded by their watch with a healthcare provider. However, by default, cycle tracking data stays on the device and is encrypted when the user's iPhone is locked with a passcode, Touch ID, or Face ID. Compared to Samsung's Galaxy Watch 5 series, Apple is forthcoming about how the temperature sensor on its new watches will work. Samsung has been vague, and perhaps, this might be because the sensor doesn't work right out of the box but will be activated in the future. However, it did say that the sensor will "provide users with an in-depth understanding of their wellness."
Source: Apple