Can I safely delete from my iphone photos shared by friends? I would like to free some space on my iPhone 4S by deleting my local copies of photos from a friend's photo stream. Can I do that without affecting my friend's originals and without signing out from the stream? Ideally, I would like to do that selectively, i.e. delete some of the photos and keep others. Also, I would like to continue to receive my friend's newer pictures.
Photos of a shared stream can only be deleted by the owner thereof. Once deleted, this photos will be automatically deleted from any device of anyone subscribed to the stream. 

The photos you've previously saved to the Camera Roll, for instance, won't be deleted, though.