For now, not much is known about Pokemon Sleep. We know this is an upcoming game that will track sleep and offer some form of reward. The company made it known that the game is focused on making sleep a form of entertainment during a press conference in May 2019 in Tokyo, Japan.
Pokemon Sleep is believed to be released around summer next year on Android and iOS devices. So if you have any of these devices, you will be able to get Pokemon Sleep when it is released.
To use the mobile game, you will also need the Pokemon Go Plus+. The accessory will communicate data to the user’s mobile device through Bluetooth.
Currently, Pokemon sleep is being developed by Select Button with some assistance from the developer of the Pokemon Go mobile game, Niantic.