Smart Ball is an Action-adventure game for the Super Nintendo Entertainment System, known as Jerry Boy (ジェリーボーイ) in Japan. A sequel called Jelly Boy 2 (ジェリーボーイ2) was in production, but was never actually released.

The player controls a young boy named Jerry, who was a prince and ruler of a kingdom. Jerry has been transformed into a blob by a mysterious wizard at the behest of his jealous brother, Tom, who has a crush on the young princess Emi. In that incarnation, the player plays as a little jelly bean with eyes, travelling across a photorealistic grassy landscape. The game has graphics and terrain that are characterized as cartoony and cute, which attracts younger players.

The player is able to defend Jerry or attack enemies by controlling certain physical characteristics of Jerry, such as flattening or stretching his body in order to hit enemies, or by finding objects, such as balls, to throw the enemies. The player can also run by pressing the Y button on the controller. Jerry has the ability to stick to walls and ceilings by holding down the Y button as you jump towards them, adding an advantage over Jerry's enemies. The player advances through each level along a filmstrip map, and can revisit previously-completed levels by "rewinding" the filmstrip. Each level is a romp up and down hills, jumping between platforms, and squeezing through pipes. Scattered around each level are a number of plants that open up to reveal balls, power-ups, 1ups, seeds and jumping enhancers. Similar to Donkey Kong Country, the player must collect letters that spell JERRY in each level. Collecting them all will give the player two extra lives.

Sony removed the entire storyline from the game, as well as all the towns in levels, in the North American version. However, the English translation patch of the Japanese version with scenes is playable on an emulator.