I want to change a specific value in my app.config appSettings for my Cloud Service Worker Role. I don't want to republish my service so as to allow it to keep running. How can I do this either from Visual Studio or Powershell or any other tool?
You can only change values in the ServiceConfiguration.cscfg file without a redeploy, so it is recommended to store the settings in that file, instead of app.config, for a Cloud Service.
https://azure.microsoft.com/en-us/documentation/articles/cloud-services-how-to-configure/