New Amazon wristband will be able to detect user's emotional level, visualize body fat

Amazon is hoping to break into the fitness-tracking scene with a new device announced this week that will be able to monitor a user's emotional state, among a range of other abilities. 

The Amazon Halo, which will go up against the FitBit and the Apple Watch in the "activity tracker" market, will offer standard features of that class of product including daily step tracking, heart-rate monitoring and other health-related metrics. 

It will also offer features such as sleep scores, which each morning will grade the quality of a user's sleep.

Among the device's more notable offerings will be its capacity to track a user's emotional state by monitoring voice tones via on-board microphones. Users will be able to look back over the course of a day and note times at which they may have felt stressed, happy or angry.

The company states that the wearer will be able to "analyze qualities of [their] voice like energy and positivity to help strengthen communication."

The device, which is waterproof and meant to be worn all the time, will grade users' progress by way of a point system. The wearer will gain points by doing more exercise and lose them by remaining sedentary too often. 

The Halo will also permit users to "measure and track body fat," even allowing them to "see [themselves] at different body fat percentages with a personalized 3D model."

The device will charge users $3.99 per month for its services.