I have used the relative path location in this project.
An absolute file location couldn't be created AT ALL - the CSV wasn't created and couldn't be read. The app only works if the location starts with '/' or just the file name - as said in the link.
I have looked through all phone files and it is nowhere to be seen. I have tried to copy the file location and find it that way on my phone - no avail. Since I tried so many times with different file locations I thought it should have been created at least somewhere.
I have saved the app on my phone and downloaded it etc to see if that helped and it didn't.