For most applications you can look close to the footer of the home page and you'll find a link to whom the application was "Created by".
With an application that uses a sidebar it is trickier! Generally these are intended for solo users to post, but the most prolific poster is generally the owner. You can reach them through the link/avatar beside their posts.
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.