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Sharing technologies
GuitarTuna: Tuner,Chords,Tabs
Yousician Ltd.
临吉他调谐器 Pro Guitar Tuner
ProGuitar
Guitar Tuner Guru
Tabs4Acoustic - The only guitar tuner you need
Guitar Tuner - Simple Tuners
ZipoApps
Simply Guitar - 吉他陪练
Simply (formerly JoyTunes)