Tuner XR(Tuner with eXtRa featrues) is an application for musicians who play vocals, instruments and more. The Tuner XR allows for a variety of tunings from the Baroque to the modern era. Meet powerful tuners such as just intonation tuning and differential tuning systems. And you can conveniently view my tuning history in graphs and tables. There is also a sound frequency table at your convenience. - Tuning specific notes for equal temperament and just (pure) intonation. - You can tune based on various frequencies rather than a fixed frequency. - Frequency (pitch) table at which notes can be sounded. - Stats to record and view your tuning results. There are other convenient features as well. - Universal design for all models of iPad, iPhone and iPod touch (7th generation). - Synchronize the tuning record results between my Apple devices through iCloud. - Support dark mode.