HD Theme 2021 is a personalization app for Android devices that provides a wide range of themes and icon packs for Neox Launcher users. The app offers a collection of black HD wallpapers and icons that enhance the look of the home screen and lock screen. The app also includes a clock widget that displays time in a stylish way.

With HD Theme 2021, users can update their Android version to a beautiful theme with a new icon pack for free. The app is compatible with the latest Android updates and supports all Android phones. However, it's important to note that HD Theme 2021 is not a standalone app but an icon pack for Neox Launcher. To apply the icon pack, users need to install Neox Launcher from the Play Store.

The app allows users to apply free themes in a single click, making it easy to customize the look of their Android mobile in a cool style. It is developed by Wallpapers and Themes and is available for free download. Users can support the developer by giving ratings and comments, which will inspire them to develop more free themes.