ChemdrawJS Online is a sample version of the original chem draw which is freely accessible to all as of now.
Can we add a link to this on the help page? It should help a lot in encouraging new people to start using it.
I vote against adding ChemDraw JS to the Help Center.
First of all, adding a single editor creates a false impression of a de facto standard, which it is not. Users need to have freedom of choice and be aware of the alternatives. If anything, adding link to the Software answer would be the right choice.
Second, by mentioning a product on the official help page means Chemistry.SE promotes its usage. Promoting free and open-source programs because they rarely get enough coverage seems like a good deed to me. A commercial product, on the other hand, is backed up by the PR team and ads. I don't see the point in shilling a commercial product risking your reputation, especially for free.
Finally, never use an online service for anything remotely serious. Drawing complex chemical structures on a regular basis with consistent appearance seems serious enough for me. With online products you have absolutely no control over it. It could be taken down, change its terms of service, collect your data and you can never know in advance what's going to happen and you have no means to fix a problem. On top of that, it all relies on an internet connection. Maybe I'm too old, but I never include online services in my workflow. To me, they are toys, not tools, and I will never willfully encourage new people to use them.
Funny enough, http://perkinelmer.com is not available at the moment suggesting to visit them on Monday. Keep in mind you can see a similar page one day you need to quickly draw a reaction scheme with ChemDraw JS.