JO1 is a mobile game that revolves around the story of 11 star princes who unexpectedly land on Earth and start living together. As a player, you get to communicate with the JO1 members and increase your love rank by playing the game's communication part, called "Process." This will help you progress through the story and get to know the members' real personalities.

In addition, you can use cards to set up the chibi JO1's "Star Live" and make their performance the best it can be. You can also deepen bonds by giving gifts when you visit their rooms. This will help you get special stories and rare rewards. JO1 is a free game, but some items may require payment. It is compatible with iOS 12.0 or later and can be played on iPhone 6s, iPad Air 2, iPad Mini 4, and later devices.