When you click ‘Choose Account to Migrate’ button you will see a list of accounts. Select the ones you want to migrate photos from. After you have selected the service from where you want to migrate photos, select the services where you would like to migrate photos and videos too.The final step is to click migrate button at the bottom of the window.
PicBackMan is a free photo/video uploader that helps you to keep your memories backed up to your favorite online services.
Users in 130+ countries have backed up.
... an excellent job of uploading more then 300GB of photos to 2 different services