What's the name of Andhadhun introduced in The Return of Guo Mu Prodigal Son?

You mean what kind of tuning software does Mr. Guo Mu use to tune the guitar in class? You can search directly in the application download. Guitar tuning is a sign in the shape of a green+yellow pick, called Guitar Tuna.

That is, as shown in the picture, both Android and Apple systems can be downloaded.

If you want to buy an electronic tuner, you can go to the teacher's official shop, which is the fruit tree prodigal son certification mall!