Copy the APK into your SD card and run it. It will install apps with the name ext4.
You might have problem where the ext4 manager will tell you that your system is out of storage when it tried to restore. What should I do? Clear system storage by removing a few Samsung apps using Nitrality. Download here. Once you get "/System" nearly 6MB FREE your ext4 manager should be able convert your files to ext4.
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