Easy Piano Tuner

Developer's DescriptionBy Willey PianoA user-friendly app for tuning pianos to a professional standard.Easy Piano Tuner is a piano tuning app that will transform your Android device into a professional quality electronic tuning aid. Unlike regular chromatic tuning apps that simply tune to a pre-calculated equal temperament, this app actively measures the tonal characteristics of each note and automatically calculates the ideal "stretch" or offset from equal temperament. In other words, it creates a custom tuning for your piano with the best compromise between intervals like fifths, fourths, octaves, and twelfths, the way aural piano tuners do when fine-tuning.There are three levels of functionality: a free (evaluation) version, a paid "plus" version with basic tuning functionality, and professional version with features geared towards professional piano tuners. The extra functionality is unlocked through one-time in-app purchases.The Free version includes the following functionality:- Tuning functionality for the mid-range of the piano only- Automatic note detection- Ability to measure each note on the piano to see how its current tuning compares to the ideal tuning curve (see if a piano is roughly in tune)- Swipe in the graphing area to show a live frequency spectrum or the inharmonicity of measured notes.Upgrading to "Plus" adds the following functionality:- Tuning functionality for the entire piano- Tune to frequency standards other than A=440- Calibrate device to an external frequency sourceUpgrading to Professional unlocks all features of the "Plus" version, plus the following:- The ability to save and load tuning files, so a piano doesn't need to be re-measured each time it is tuned- Pitch raise mode that calculates overpull for an initial first pass "rough" tuning (for pianos that are extremely flat)- Access to all future features and enhancementsUpgrade costs:Free to Plus (approximately US$20)Free to Pro (approximately US$100)Plus to Pro (approximately US$80)Note about permissions: This app requires permission to access the microphone on your device and permission to read and write files.