The use cases:
1) Please read the citation of Hans Garon in the next article.
2) A drawing tool like www.bobsprite.com (not for smartphone).
The browser inside a browser:
The purpose is to describe how simple are the *algorithms of the browser interface*. And for VERY SPECIAL cases, provide a useful and easy library to do everything with one canvas only.
Using only the canvas, you can do ALMOST anything, including responsiveness to window size and zoom. But, obviously, a screen reader is not supposed to read the content of the canvas. Also, the canvas cannot play sounds.
Try the sample of the series (not for smartphone) a full app inside one canvas :