Android is a mobile operating system developed by Google, primarily designed for smartphones and tablets. It is not commonly used in smartwatches.

watchOS is a proprietary operating system developed by Apple specifically for its Apple Watch smartwatch.

Tizen is a Linux-based operating system developed by Samsung. It was previously used in Samsung's smartwatches, but has since been replaced by Wear OS.

Wear OS is a proprietary operating system developed by Google for smartwatches and other wearable devices.

Gaming is not a common app category available on smartwatches due to their limited processing power and small screen size.

Fitness and Health apps are designed to help you track your physical activity and overall health.

Messaging apps allow you to communicate with others using your smartwatch.

Navigation apps help you find your way around and provide directions.

Garmin is a popular brand of GPS devices, but it is not as well-known for its smartwatches as the other brands mentioned.

Fitbit is a popular brand of fitness trackers and smartwatches.

Apple is known for its stylish and feature-rich smartwatches, such as the Apple Watch.

Garmin is known for its rugged and outdoor-focused smartwatches, such as the Garmin Fenix series.

The Garmin Vivoactive is not as popular as the other smartwatch models mentioned.

The Garmin Vivoactive is known for its long battery life, which can last up to several weeks on a single charge.

The Apple Watch is known for its advanced health tracking features, such as the ability to measure blood oxygen levels and perform an electrocardiogram (ECG).