Below is a technique to create a 'Back' button within your Tumult Hype document which will take your users to the last visited scene. This does not override the Browser back button.
First, on all scenes where you want to remember visits, add this JS function to run 'On Scene Unload':
window.lastHypeSceneName = hypeDocument.currentSceneName();
To create your back button which will look at the last 'Unloaded' scene, run this function when the button is clicked:
if (window.lastHypeSceneName == undefined)
// do nothing.
Other scene transitions can be found here: http://tumult.com/hype/documentation/3.0/#api-constants
Here's a downloadable example:
backtopreviousscene.hype.zip (14.1 KB)