A chime. A toast notification: “Nova Prime unlocked. Welcome back.”

For users running legacy hardware on Android 4.4.2 KitKat , Nova Launcher remains one of the best ways to modernize the user interface and improve performance. While modern versions (v8.0+) require Android 8.0 or higher, you can still achieve a smooth, premium experience using older stable builds. Compatibility for Android 4.4.2

Deep in the Prime settings was a feature that predated modern folder management:

Your old phone isn't obsolete – it’s just waiting for Nova Prime.

The free version of Nova is great, but the (paid) APK unlocks features that specifically address Android 4.4.2’s shortcomings:

: Nova Launcher Prime acts as a license key and does not have its own "version" in the traditional sense; it unlocks features within the main Nova Launcher app. Where to Find it