Every thought of making the circles for retina displays?

[emilkarl]

[kottenator]

You could make it twice bigger in JS config but then resize the canvas to 50% size with CSS.

There was a similar issue about responsive design, please check if it would help.

And I would appreciate if you will advise a better way to do that, because I don't like the one I proposed.

[kottenator]

I hope I solved your problem. I'm closing the ticket