Chordify - Chordify turns any music or song (YouTube, Deezer, SoundCloud, MP3) into chords.
Headspace - Meditation made simple. Brilliant things happen in calm minds.
muted.io - A magical collection of interactive music theory tools & visual reference pages for musicians and music producers
Calm - Calm.com can help you reduce stress and increase calm.
soundrop - Soundrop is an app that allows you to create your own personalized sound track to keep you focused or relax.
Medito - 100% Free Meditation App that will improve your Mental wellbeing with the help of Guided Meditations, Breathing Exercises, Mindfulness Practices, Relaxing Sounds, and more.