Drive In! is a casual game that belongs in the 'idle clicker' sub-genre, where the aim of the game is to serve as much food as you can at your drive-in restaurant.
Gameplay in Drive In! is typical for the genre: you're the owner of a fast food restaurant. Cars will appear on the road, pass by your restaurant, and order food. Your objective is to manage your restaurant's resources, prices, and earnings strategically to maximize your profits. You can also level up your restaurant to get more customers, charge more for food, buy better ingredients, etc.
As in other games of this type, you'll automatically earn money from the cars as they appear, but you can also increase your earnings by tapping on the restaurant. This way, you can keep earning money even when there's a slump in customers. Then, you can use your earnings to level up, marking up the prices or making people eat faster.
Despite its spare design and simple gameplay, Drive In! is an excellent game that's tons of fun to play.