Storage Isolation, previously known as Storage Redirect, is a utility tool developed by Xingchen Rikka for Android devices. It requires root access and is not a free app. However, you can enable isolation for up to three apps to test if it works on your device.

This tool allows users to isolate an app's storage access, meaning that the app can only access its own files and not the files of other apps or the system. This feature can be useful for privacy concerns or to prevent certain apps from accessing sensitive information. Storage Isolation also provides an easy-to-use interface to manage the isolated apps and their storage settings.

Overall, Storage Isolation is a powerful tool for advanced users who require more control over their device's storage access. However, it is important to note that this app requires root access and is not recommended for novice users.