Wallpaper setting is buggy.
a) When trying to add my own photos, I have to tap one at the time (but isn't always added to my wallpapers!) When I select multiple photos in my collection, there is no button to include them all.
b) Trying to delete a photo from my selected wallpapers, the X in the top left corner seemingly deletes the photo, but when I come back to my wallpaper settings, the deleted photo is still there. Now I have a number of duplicates and no way to delete them. When I tap on these photos that are still there despite having deleted them, I get the message "Unable to load wallpaper. Unfortunately the image is currently unavailable.
To summarize: the behavior is erratic and counter-intuitive.