Fine Lock is a useful tool for customizing and optimizing the Android experience on Samsung devices running official Oreo and One UI. It acts as a launcher for Good Lock and Galaxy Labs modules, which are official tools for customization. However, Fine Lock does not support Samsung devices running AOSP OS build, such as LineageOS. It is important to note that One UI Core models are no longer supported by Samsung. Due to compliance with Google Play policy, Fine Lock cannot download any modules for you. Instead, you can get the latest APK modules from trusted sources like APKMirror or Sammobile. The PRO features of Fine Lock include module app shortcuts on the home screen, background check for updates, hiding modules that are not installed, and dynamic wallpaper that changes based on the device's Dark/Night modes. It is crucial to ensure that you have the latest version of Fine Lock installed before making any purchases. If the PRO features are not unlocked within minutes after purchase, you can contact the developer with your Order ID, which can be found in an email from Google Play. Fine Lock is specifically designed for Samsung devices running official Samsung's Android and Android + with One UI. It may not work and could crash on devices made by other brands. The sample screenshots showcased in the app are created by marikit.