Normally, any deleted file has its name removed from the folder and its storage space is added to the "freely available" list for recycling. The actual data that was in the file still exists on the file system until that space is overwritten by a new file. This is normal for any modern computer file system.
"Undelete" programs work by scanning the "freely available" list and scanning the raw storage sectors.
To "permanently" delete a file, you need a security program that will overwrite the old file space so that there is nothing for an undelete program to recover. Lots of these exist for your computer; I know of none for your phone, but I have never looked for one either.
Some file browser apps implement their own "recycle bin" which allows the file browser to undelete the files it deletes. This is done by simply moving the old file to a hidden folder instead of actually deleting it. Later the file browser app will actually delete the file based on a time limit or maybe on available storage space.
01-02-2018 12:14 AM
