Your OneSignal account supports one or more applications. All Applications provides an overview of each application in your account, including the total users and subscribed users in each app as well as the different platforms that are supported by your application. You can access this page by clicking the OneSignal logo in the top navigation bar.
Clicking on an app brings you to an individual app's Dashboard
Clicking on the options menu brings up a menu allowing you to rename or delete/Remove your application.
Deletion is Permanent
If you delete your app, there is no way to restore it!