The "stock" SharePoint approval workflow comes with custom InfoPath forms that enable a nice "Open this task..." button in Outlook that displays an approval form right in the Outlook.
However if I design a custom approval workflow in Visual Studio 2015, I cannot get anything like that; the CombinedTask activity does not seem to expose any properties that would allow associating the task with any custom forms.
Having done some googling, I came to realize that I would need to create custom InfoPath forms from scratch and link them to the workflow tasks somehow, but I haven't been able to find any reasonable tutorials on how this could be achieved in SharePoint 2013.
The only relevant post I was able to find was this: Custom Task Forms created in InfoPath for Visual Studio Workflow but that one was for SharePoint 2010.
Does the content of that post still apply to SharePoint 2013 (barring the version numbers and things like that), or should I approach this at a completely different angle? At the first glance, the described approach uses some C# code which automatically makes it not applicable for a SharePoint-hosted add-in scenario.