Phone Master is a free Android app developed by ADAM T HENNICK that helps manage useless junk files and displays the status of your Android phone. The app requires MANAGE_EXTERNAL_STORAGE permission for file management, and if the permission is not granted, file management will not be possible.

The main features of Phone Master include managing junk files, such as cache files, temporary files, and obsolete APK files. The app also displays the status of your phone, including CPU usage, memory usage, and battery status. The interface is user-friendly and easy to navigate, making it accessible for users of all levels of experience.

Overall, Phone Master is a useful app for those looking to manage their Android phone's storage and performance. However, the app's reliance on the MANAGE_EXTERNAL_STORAGE permission may be a concern for some users.