Apex Launcher has not been actively maintained since v4.x (beta). Version 3.3.3 is no longer available on Google Play . Any APK you download comes from third-party sites.
Apex Launcher is a customizable launcher for Android devices that allows users to personalize their home screen, lock screen, and app drawer. With Apex Launcher, you can change the look and feel of your device, add new features, and improve performance. apex launcher 3.3 3 apk download
While version 3.3.3 was primarily a maintenance release, it finalized the stability of the 3.x branch: Download Apex Launcher Classic 3.3.3 Android APK File Apex Launcher has not been actively maintained since v4