Hello dear sir , I understood your requirement and can deliver the application to you ,
working will be as follows:
1:main screen will be having on option to choose the file,
2:then all the files path will be stored in database,
3:you can anytime deselect the files
4:option to choose the time interval for deleting files
5: app will run in background and will delete the files on regular basis
hope to discuss the project in detail with you.
kind regards