Slot machines used to be massive, bulky cabinets often topping 40 inches tall...

https://spencersnewinsights.capitaljays.com/posts/what-is-a-slot-machine-top-box-and-what-is-it-for

Slot machines used to be massive, bulky cabinets often topping 40 inches tall and weighing hundreds of pounds. Now, these games fit neatly on 6-inch phone screens, making it easy to spin reels anytime without dedicating a whole floor space