To remove the Smartcode application from your Android device you'll need to enter settings.

You may be able to swipe up on the home screen to show the app drawer.

If this does not work tap the app drawer button:

 

Then navigate to Settings

App & Notifications (on some versions of Android it's called "Apps")

Then locate the Smartcode app and tap on it (on some versions of Android you will need to tap "See all apps" first)

Then tap uninstall

And OK