The reason it lags is because of this (possible) assumption. The application needs full network access in order to work. Which means the dev probably just created a linked web app.
How this works? You create an app with no actionbar and remove the controls. In the code direct the app to a URL with WebView and give it internet permissions in your Manifest.
Outcome - You get an app the automatically redirects to a URL that was in the code, in other means. The URL for the Polymer Calculator example.
Anyways, its still nice though.
iOS7 Kik Messenger | Svelte UI CM11 Theme | Active Launcher