Guitaa is a free online music platform for musicians, that lets them find chords of any song of their choice on Guitar, Piano and Ukulele.
App:
Perfect app for musicians
Band-in-a-Box - Band-in-a-Box is so easy to use!
ChordU - Extracts chords from any song, integrated YouTube.
iReal Pro - iReal Pro – Music Book and Backing Tracks is a commercial music app developed by Technimo for Android and iOS devices.
Chordify - Chordify turns any music or song (YouTube, Deezer, SoundCloud, MP3) into chords.
ChordMill - Music play along app for all instruments and voices
yalp.io - Automatic chords extraction from mp3 and YouTube