I am looking to take an image binary and save the file to local storage on a phone (android phone)

It appeared that FilePlugin was ideal for this application, however I can't get the SaveFile function to work.

I get a mystery extensionless "file" called "hubManager" saved to the main directory of the phone, but I can't get an image file to save to any specific location.

Can anyone offer advice as to ho to correctly use this extension? Unfortunately my experience with javascript is very limited so if possible I am looking for a low code solution.