Ball Sort is a sorting game that features classic play with laboratory test tubes. The player sorts colorful balls into matching stacks inside of flasks. Their goals are to unlock new levels and earn as many coins as possible.
Each level contains two or more test tubes or other flasks filled with stacks of mixed-color balls. The player rearranges the balls by using empty flasks and partial gaps above some shorter mixed stacks. Although they can place a ball or short stack of any one color into an empty flask, they can only transfer one or more matching colored ones to the gap above an existing stack. For example, they can only place a blue ball into a gap above another blue one. The game auto-splits any one-color stack that's larger than the gap space.
The player also uses boosters, including a flask icon that adds part of a flask or an entire one to the playfield, a semicircular forward arrow button that reloads a level, an opening button that temporarily installs a flip door in the bottom of a flask, and a back arrow that reverses a previous move. On some levels, they also receive a hint booster marked with a magnifying glass and a question mark that temporarily reveals all balls hidden behind black paint.
Ball Sort rewards the player with coins at the end of a level. The player also earns coins from three-win gift boxes, star treasure chests, daily challenges, daily bonuses, and new title achievements. They can collect extra coins by viewing ad videos. They then use their coins to upgrade the ball, flask and background designs. For example, they can choose lollipop tops, soccer balls, hearts, beach balls and other skins for the balls.