This video illustrates the utility of Microsoft Flow in being able to address a (current) limitation of PowerApps - namely support for handling photo uploads. This method involves no custom code, and can handle setting SharePoint metadata as well as handling other media like audio recordings from PowerApps too. For a sample Swagger file that you can use, visit this article...
http://www.cleverworkarounds.com/2017/11/13/a-sample-openapiswagger-file-for-powerapps/
