Sources to Investigate

Sound Cloud

Sound Cloud in Education:

YouTube

Hypothesis

Above: Hypothesis with an annotation

Above: Hypothesis with a Note.


Ant - Video Annotation Tool

Website: https://ant.umn.edu/

Description:

The image above:

Other notes:

W3C Web Annotation

W3C had a Web Annotation Working Group until early 2017. The goal of the group was "to develop a set of specifications for an interoperable, sharable, distributed Web Annotation architecture."

https://www.w3.org/annotation/

"Traditional annotations are marginalia, errata, and highlights in printed books, maps, picture, and other physical media. Web annotations are an attempt to recreate and extend that functionality as a new layer of interactivity and linking on top of the Web. It will allow anyone to annotate anything anywhere, be it a web page, an ebook, a video, an image, an audio stream, or data in raw or visualized form. Web annotations can be linked, shared between services, tracked back to their origins, searched and discovered, and stored wherever the author wishes; the vision is for a decentralized and open annotation infrastructure."

This article "Three recommendations to enable annotations on the web", by Coralie Mercier (Feb 23, 2017) summarizes 3 key components to the architecture:

The same article also includes a link to a document outlining how Web Annotations can be implemented in HTML.

Diagrams:

Drop in and out collaborative creations

Collaborative creation examples: Google drawings, Minecraft, Scratch

Features:


Other commercial online collaboration tools

https://redpen.io/

https://conceptboard.com/

https://govisually.com/

https://scribblar.com

Flickr

Flickr used to have a photo annotation tool called "notes", but this may not be a feature anymore. 

For example, see this image with the notes feature.