Suoni is an app for online piano lessons with live teachers. The app contains a video call with adjustable view from multiple cameras and a collaborative sheet music, a marketplace, lesson booking system and a music library. A student books a lesson when the teacher is available and go to the virtual classroom when the time is up. The teacher can properly see the posture of student's fingers over the keyboard and remotely explain the playing technique. The student can see the notes the teacher took on the sheet music and review them during home work.