Niantic has posted an update on their blog that says that Nintendo and The Pokémon Company will release Pokémon GO Plus on September 16, 2016, in most countries. (It will be released in a few South American territories later this year).
Pokémon GO Plus is not a new version of, or an expansion of, Pokémon GO. Instead, it is a wearable device that players can use to play the game.
Pokémon GO Plus is a companion device that connects to your phone over Bluetooth Smart (the Bluetooth low energy connection designed for health and fitness applications), allowing you to keep your phone in your pocket and go about your day-to-day activities while still being able to collect valuable resources and capture even the most elusive Pokémon.
Niantic says that Pokémon GO Plus will “allow you to blend Pokémon GO more seamlessly into family and fitness activities.”. They point out that the wearable will let you go through your day, and play Pokémon GO, without having to look at your screen all the time.
The Pokémon GO Plus device will vibrate and light up to alert you to the location of a nearby PokéStop. Players can click the Pokémon GO Plus to collect items from the PokéStop. The device will also light up and vibrate if there is a Pokémon in your area. You can catch the Pokémon by using the Pokémon GO Plus, but you won’t know which Pokémon you caught until you look at the in-game journal later on.
The Pokémon GO Plus was first announced in September of 2015 when the Pokémon GO game was officially announced.