SanDisk Dual Drive Luxe USB 256gb copy question

I bought my wife this product because she takes thousands of photos on her iPhone and wants to copy some of them to her PC.
My question is, do the photos stay on the phone when they are copied to the drive or are they all moved to the drive and removed from the phone?
Thank you.

haha It depends on what option she chooses when she selects a photo or album. Move removes them from the phone, copy leaves them on the phone.