WordDraw enables you and your visitors to draw comments.
Algorithm is pretty simple: a visitor drawing picture then it encoded in Base64 and saving in database. After that you can edit or delete it in WordPress admin as ordinary comments.
Note that when you disabled plugin, all drawings will be displayer as abrakadabra:
WordDraw will work in most modern browsers. It tested in Internet Explorer 8, Safari (including iPhone/iPad), Firefox, Opera, Chrome. We also planning support IE 6-7-9 after beta release.
For unsupported clients, canvas will be disabled and replaced with default editor.
It seems, nope. WordDraw does not create additional tables, queries or files. Images are encoded in Base64 and stored as text in database. So the only problem may be if the browser incorrectly handled these images. But it's unlikely.
Yes, soon. WordDraw is based on Drawform project. Even more WordDraw is just convenient interface for Drawform. DF is in active development, so they release source code and API documentation soon.