Amazon’s first health wearable is no Fitbit or Apple Watch clone

Rather than trying to be a smartphone for your wrist, the $99 Halo is a sleek companion to an app that measures your body fat and gauges your tone of voice.

Amazon is launching Halo, a minimalist $99 health wearable and app aimed at helping people stay healthy. Executives who worked on the project say that the offering is more about the app and its various features than the wearable itself.

Customers can preorder the Halo band for $65, which includes six months of access to the app. After the first six months, customers will have to pay $4 a month to continue using the app. Once it ships in a few weeks, Halo will be $99,...