This feature is build on top of the existing QuickStart Apps capability, a very nice feature which part part of the very first release of Oracle PCS.
So let's see how you can create a very simple application in Oracle Process Cloud Service and how you can promote it as a QuickStart app.
Create a new application in Oracle Process Cloud Service, give it a name and file it under a space (I've named it "Travel Request Application" under a custom space called "aantoniou").
To do so, from the "Application Home" click on the elipse button (denoted by the three dots) and choose "Convert to QuickStart Master".
Expand the "Properties" section and choose an image to be used for your QuickStart App.
Depending on the component type and the actual item selected, you have various properties which can be flagged for customization. In my case where I've selected the "Start" activity component, the only properties available for customization is the title (if you switch component type and item, for example lane and choose one of your lanes, you should see the "Role" property available for customization).
Click on "Done" and save your work. We are now ready to promote our QuickStart Master as a QuickStart application. To do so click on the "Promote" button. On the "Request to Promote as QuickStart App" properties window define a name and click "Promote"