Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
SoundGrail - SoundGrail Music App designed for pianists, guitarists, and DJs.
GarageBand - GarageBand is a fully equipped music creation studio for Mac
keezy - A colorful soundboard. Play with music.
Adobe Audition - Mix, edit, and create audio content in Adobe Audition CC with a comprehensive toolset that includes multitrack, waveform, and spectral display.
Splice - Music creation, collaboration, and sharing made simple.