Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
Easy Microphone - Easy microphone is an app that turns your smartphone into a microphone for those devices that don’t feature a built-in microphone.
WaveShop - Open source audio editor
Audio Editor Tool - Audio Editor Tool enables you to make high-profile changes to your audio and music files.
TwistedWave - TwistedWave is one of the unique audio editors that allow you to edit your music file online without any installation.
Iriun Webcam - Use your phone's camera as a wireless webcam in your PC or Mac.