When I changed from my iPhone to my Samsung S8, Samsung was nice enough to provide a little program that copied all doc and media files (including all my music) to my S8. Went flawlessly. Now all my music is in the iphone/music folder. Photo's are in the iphone/Pictures folder.

But I see there is also a DCIM folder and a Music folder in the root. I can see the DCIM folder holds all the photos take with the Samsung S8. The Music folder currently holds no files since I didn't copy any to it yet.

But I was wondering: when apps use photos, videos or music, they find ALL photos, videos or music, even though the files are scattered in different folders. Where in the system is it determined which file goes where, where the system needs to look for certain files and can you alter that? (probably yes, it's Linux, but where?)
Also, this probably means I can freely copy files between these folders?
I'm asking because I would like to add a 128GB microSD card to the S8, and then copy all music to there. Can I simply and safely cut and paste the music from the iphone folder to the SDcard?

Thx!

I'm not certain, but if Android sees new photos in a user-created folder it might ask or assume those items belong with the other photos.

*edit*
When you insert the SD card, I believe Android will ask if you want to use that as the primary storage for photos taken with the camera.

You can decide where photos take end up but tools like the Gallery tend to find any photos any where. This is a bit of aproblem if you have files that aren't photos and they all tend to show up as "albums"

Music depends a bit on which music application you use. Something like Poweramp lets you pick the specific location of files you want to use. Google Music lets you pick internal or external (i.e. plug in SD card) to store local copies of files.

Sometimes, when manually copying photos from a computer, or moving them between folders on Android, the system doesn't seem to notice the new files.

The solution to this is to force a "media re-scan". Rebooting the device is supposed to accomplish that, but there's also a nice app at the Play Store which gives one more direct control over it.

Actually, there are several such apps, but the only one I have tried that works reliably for me here is called "media.Re.scan" by Hiroyuki Mizuhara.

Thanks guys!! I've now got a different problem. I want to create some playlists from the music files on my microSD card. This works pretty simple in windows, just go straight to the S8 -> card -> folder, the right click and select "create playlist". It then creates a .PLA file straight on the SD card, as it should. Problem is, this type of file works with only a few players. I've got the feeling that m3u files would be better, but I can't seem to find a way to easily create them.

Using PC programs like Foobar2000 or Winamp, it seems it's impossible to add complete folders from the S8 via USB to these programs. This probably has got something to do with the way USB transfer works on Android phones. So I can't create playlists that way and save them directly to the microSD card.

So next I tried .PLA to M3u converters, but those don't seem to exist?

Another option would be to remove the microSD card from the phone and use it in my cardreader, but that would become tedious very quick if I would have to do that everytime I want to create a new playlist. (not to mention the wear and tear on the S8 microSD card slot)

Does someone have another option for me? Basically I just want to be able to use my PC to create playlists from the music files on the S8, for use on the S8. Thx!

An M3U file is a plain text file with a list of filenames in it. Other than the mechanics of getting the file onto the SD card, you don't need any special tools to create one.

I know, but what I want to do is create an M3U file from the files on the S8, when it's connected to my PC via USB, via Windows explorer. After which I would then copy the generated file to the /playlists folder of the S8. That doesn't work because for some reason I cannot simply use the S8 as a mass storage device and do what I want with the files. Eg. I can play a file (on the PC from the S8) one by one (or drag one into Foobar 2000/Winamp one by one), but not two or more files, let alone an entire folder. And this is what I want to do, because doing this one by one is tedious and not very efficient. It's also not that different from creating the playlist on the phone itself, file by file. Maybe this is a Windows thing, I don't know. It might pay off to install a Linux distro in a VM and see if the effect is the same or not. I'll try that now.

IIRC, Android phones sometimes have ways to switch the USB modes from Mass storage, to camera like, to developer modes. I’m blanking on the exact terms, but remember that being an issue on my Samsung Galaxy ages back on my Mac and with some automated tests at a past job. For some reason I had to manually flip the USB mode to change between where iPhoto would see photos, and where I could see the music folder.

Maybe something similar is going on here between Windows and the S8? I think it was the pull down notification tray that offered the ability to switch USB modes on that old Galaxy.