Which hardware device did Microsoft release in 2014 to compete with fitness trackers?

The hardware device Microsoft released in 2014 to compete in the fitness-tracker market was Microsoft Band.

Microsoft announced the Microsoft Band on October 29, 2014, and released it in the United States the following day. It was a wrist-worn smart band combining activity-tracking and smartwatch features. Its sensors could support measurements and tools related to steps, exercise, sleep, heart rate, and guided workouts, while its display delivered notifications and other information.

A notable part of the product's strategy was cross-platform compatibility. Microsoft Band connected over Bluetooth to Windows Phone, iPhone, and Android devices, rather than being limited to Microsoft's own mobile ecosystem. Microsoft paired it with a companion health service that used collected data for fitness and wellness features.

The device was not the same type of product as a traditional smartwatch, although it borrowed some smartwatch functions. Apple Watch arrived in 2015, while Fitbit and Pebble were already established competing brands. Microsoft discontinued the Band line in 2016 after also releasing a second-generation model.