After designing, building, and executing your application, you should test them locally before making it available for use. You can test your application using either of the following options:
An Android Emulator or Android physical device
An iOS Simulator or iOS physical device
A Windows Simulator, Windows device, or on the machine running natively where Visual Studio is installed
Note: Using mobile devices usually gives you a better testing experience. You should always include physical device testing in your development to ensure the app works as expected before it is published to the App Store.