"Twist" cannot be stopped.
The iPhone game, which is a twist on the classic arcade game "Tempest," was released last week and has climbed in Apple's App Store each day.
It's been the top app in terms of downloads in Apple's US App Store since Tuesday, according to App Annie, an app analytics company, getting more downloads than popular apps like Facebook, Instagram, and Snapchat.
Here's a look at why it's so addicting.