It's pretty catchy
The new Pokémon™ GO Plus + device uses Bluetooth® Low Energy technology to link with the Pokémon Sleep and Pokémon GO smart device apps. With the Pokémon Sleep app, hold the main button on your accessory and place it by your pillow.
The Pikachu within your device will sing you lullabies while you drift off and act as your morning alarm. As you track your sleep data, you’ll draw in more Pokémon that share your sleeping patterns. Befriend these Pokémon with tasty Poké Biscuits, and they may join you as helpers.
Link your device with the Pokémon GO app to spin PokéStops or throw Poké Balls automatically. This will also give you the opportunity to catch a Snorlax with a nightcap—now that’s a true expert in napping!