ScenarioJS

If you need to throw together a quick branching scenario for one of your storyboards, then ScenarioJS might be just what you need.

This free-to-use, single page web-app operates in the safety of your own browser. There are no uploads or downloads, and nothing to install on your device. Click the "Open tool" button above to open the page and use it any time, 24/7. You can also save the link in your favorites if you want to return often.