RGraph is free for all uses using the MIT license - that won't change. If you want to make a donation to the RGraph project it's appreciated. Or just linking to the RGraph website would be a big help. If you want to give feedback or suggest a feature you can do that on the feedback page. Thanks!
Martin de Bruin
Timmy Morris, ComHype Limited
American Coders Ltd, Johannes Arntz
Joseph Reisdorf, Pascal MALAISE, LastPass
Jeff Smith, Joseph Rézeau