Security · version 1.1.0
NullFile: Secure File Wipe
Erase selected files and reduce traces on free space with multiple overwrite modes.
Main functions
NullFile: Secure File Wipe on Android
- Erasing files with multiple overwrite profiles
- Cleaning up shared storage free space
- Realistic progress and clearly indicated Android limits
Full description
Find out everything about NullFile
NullFile helps reduce recoverable traces after deleting sensitive files. An ordinary delete often removes the entry from the file without immediately rewriting all the old data blocks.
Two erasing modes
- Secure File Erase: Select one or more files, overwrite them with the chosen profile, then delete them
- Cleaning up free space: the application temporarily fills the available space in Download/NullFileWipe and then deletes the temporary files
Crush Profiles
- Fast padding with zeros
- Reverse filling
- Enhanced random data
- Method inspired by NIST Clear
- DoD, HMG and NAVSO short variants
- Methods inspired by Schneier and RCMP
- Gutmann historical method
Local tracking
All actions are triggered by the user and remain local. Progress displays the percentage, current pass, and operation details.
Important Limitations of Android
No erase app can guarantee absolute physical deletion on all devices. Without root access, Android limits the application to files chosen by the user and accessible shared spaces. Internal flash memory wear management can keep old blocks out of application control.
NullFile makes recovery more difficult when the system allows overwriting, but is not a substitute for full device encryption, a factory reset, or a professional device management solution.