It has fun graphics, starting with the bus itself. You drive a bright red bus designed to look like a classic British bus. There's also cool scenery that reminds me of the countryside.
The object of the game is to drive bus passengers safely to school, which involves navigating a bridge between the mainland bus station and the island where the school is located. The bridge is narrow and difficult to navigate, so the game tests your skills in regard to timing, as well as your skills navigating the bus as you tilt your device or turn the steering wheel to drive.
You can compete against players from around the world as you collect stars while you drive. The game includes bus engine sound effects as well as background music. Many users have described the scenery of the game as relaxing. Plus, the game is optimized for use on tablets as well as phones.
I've posted before about the free games available from Universal Games. They've created a variety of fun, colorful games that are perfect for when you have time to spare and want to do something relaxing but also challenging enough to make you want to keep playing. You can see a list of all of their games on Google Play.