ChordIQ - Learn notes, chords, sight reading, perfect pitch and more.
Bandlab - Capture, nurture, and collaborate on song ideas in the cloud
muted.io - A magical collection of interactive music theory tools & visual reference pages for musicians and music producers
Krue - Twitch for music: live streams from amazing musicians
7Pad Scales and chords - Music instrument and assistant for playing scales and chords.
Vampr - Connect with musicians, industry & music lovers alike