GarageBand: a digital music creation studio featuring a sound library that includes software instruments, digital amps and stompboxes, and sound effects. Useful for creating, recording, mixing, and sharing audio files. Available on Mac and iOS, integrated with iCloud. PAID (built-in most Mac computers).
Free/Paid
Soundcloud
Soundcloud: this online audio distribution platform enables users to record, upload, and share audio files. Users can annotate audio files by inserting comments along the audio track. Mobile app available. 30 Days FREE Trial.
Diigo
Diigo: a browser plugin for your desktop and mobile devices that helps you collect and manage your internet research. Highlight text and add sticky notes to websites, take screenshots and annotate them with text and shapes. Store it all in your Diigo library, and share with others. Education accounts are available. FREE/Premium