A.P.S. Development LLC

A.P.S. 音樂工具，滿足音樂人一切所需！摘要：A.P.S. 音樂工具包括 PDF 檢視和標註工具、調音器連調音管、錄音機連播放器、拍子機、計時器/秒錶、樂器/人聲音域和換位功能、常用結他和弦、指法

The A.P.S. Ear Trainer is unique app that approaches ear-training from a completely neglected angle