Google has started to push out an update to the Google Play Store. This update introduces some UI changes rather than bug fixes or any other new features.
The Google Play Store 4.4.21 brings the slide-out navigation menu which makes it easier for the users to surf through the Google Play Store. No other major changes are observed in this version.
There were some rumors that this update will bring a more drastic card-heavy UI but this version only has a new slide-out navigation menu.
The Google Play Store 4.4.21 APK is available. It is signed by Google and upgrades your existing Play Store. It means that the file is safe to install and was not tampered with in any way. Google may take some time to push it through for various devices. Instead, download the APK and install it using any file manager.
Download Google Play Store 4.4.21 APK from here.