From what I've read this is more of an android question than this phone question. Google "where are wallpapers stored in Android" to discover all the prior answers.
Bob
Samsung S5/S6 what file location-wallpapers and locksceens
1. Where in the file system are these stored if I want to delete one or put some there manually via USB hooked to laptop?
2. Can I email myself a photo and save as wallpaper or lock screen? I assume it will go into same place?
3. Is download folder cleared or do I have to do that manually unless I do a drag and drop or cut and paste?
3. And/or is there an app to remove them instead of me having to go into the system to do so?
4. Is the file format jpg or png?
Thanks so much. I know I ask a lot of questions
Peter

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