I am aware about about Firebase Storage Extensions, but is there a method to upload and retrieve files (specifically PDF) through MIT App inventor. I want to use firebase realtime db for it. Is there a method to upload the files to some we server or directory and save the link in firebase DB? Or ca…

It will show you where it is downloaded (or not). It could be you are simply overwriting the file you uploaded, so you see no change. Give the file you are downloading a different filename...