Choosing a smartwatch or fitness tracker can be challenging due to the abundance of technical specifications and features. Understanding the differences between types of displays, sensors, and protection levels is key to selecting the perfect device that suits your lifestyle and needs. This glossary provides clear definitions of common terms, helping you make an informed purchase.
Glossary of Terms for “Smartwatches and Fitness Trackers”
Smartwatch — a multifunctional device worn on the wrist that not only tells time but also works in tandem with a smartphone. It can display notifications, receive calls, run apps, and also track physical activity and health.
Fitness Tracker — a device focused primarily on tracking physical activity and health metrics: steps, heart rate, sleep. It usually has simpler functionality and longer battery life compared to a smartwatch.
IP Rating (Ingress Protection) — an international standard indicating the level of protection of the casing against dust and water. For example, IP68 means protection from dust (6) and protection from prolonged immersion in water (8). The higher the numbers, the better the protection.
ATM Rating — a water resistance indicator showing the static water pressure a device can withstand. 1 ATM = 10 meters. However, this does not mean you can dive deeply with a device rated 5 ATM (50 meters); it is intended for surface swimming.
AMOLED Display — a type of display with an active matrix based on organic light-emitting diodes. It provides deep blacks, high contrast and brightness, and low power consumption when pixels display black (they are simply turned off).
Always-On Display (AOD) — a feature where the watch or tracker constantly displays basic information (time, data) on the screen, even in inactive mode. It may reduce battery life.
Optical Heart Rate Sensor — a sensor on the back of the device that uses LEDs to shine light through the skin and, based on the reflected light, detects changes in blood vessel volume, thus calculating the heart rate.
SpO2 Measurement — a feature that measures the level of oxygen saturation in the blood using the same optical sensor. It helps assess the overall state of the respiratory system and the quality of recovery.
Electrocardiogram (ECG/EKG) — a medical feature available in some watch models. It measures the electrical activity of the heart using special electrodes in the case, which can help detect signs of atrial fibrillation and other abnormalities.
Sleep Monitoring — a feature for tracking sleep stages and quality (deep, light, REM sleep). The device analyzes movement, heart rate, and blood oxygen levels to provide detailed statistics and recommendations for improving sleep.
Stress Tracker — a feature that assesses stress levels based on Heart Rate Variability (HRV). The higher the HRV, the more relaxed the body is considered to be.
Female Health Tracking (Menstrual Cycle) — a feature that allows women to track their menstrual cycle phases, log symptoms, and receive predictions about fertile windows and the start date of their next period.
Fluoroelastomer Strap — a popular strap material. It is a synthetic rubber known for its high resistance to sweat, moisture, UV rays, and deformation. It is hypoallergenic and comfortable to wear.
Pedometer — a basic feature that uses an accelerometer to count the number of steps taken. It is used to calculate distance traveled and calories burned.
GPS — a module for determining location using satellites. It allows for accurate tracking of running, cycling, or hiking routes without the need to take a smartphone.
NFC Module — a contactless communication technology that allows the use of a watch or tracker for contactless payments (e.g., via Apple Pay, Google Pay, or Samsung Pay).
Water Resistance WR50 — another water resistance marking, where the number usually indicates the depth in meters for which the device is conditionally rated. Similar in meaning to ATM.
Calories (Burned) — the estimated number of calories you burn per day. It includes Basal Metabolic Rate (BMR – calories burned at rest) and Active Calories (burned during movement and workouts).
Notifications and Calls — a smartphone synchronization feature that allows you to view incoming messages from messengers, email, social media, as well as accept or reject calls directly from your wrist.
Battery Life — the duration of device operation on a single full battery charge. It varies greatly depending on the model and intensity of feature use.
Wireless Charging — a way to charge the device without connecting a physical cable. Usually, the watch or tracker is placed on a special dock (magnetic pad).
Ecosystem — the software and hardware environment to which the device belongs (e.g., Apple Watch operates within the Apple ecosystem with iPhone, while watches from Garmin or Fitbit are more universal). The ecosystem determines compatibility and feature availability.