When you are browsing photos you can view them in thumbnails, list view, details view or full screen.
In thumbnail views, the photos appear as square thumbnails, organized in a gallery style and you can choose between different sizes of thumbnails. You can increase or decrease the size of the thumbnails by doing a pinch gesture. Pinch-out to increase the size, pinch-in to decrease it. There are several sizes available. In this view you can scroll up and down to view more photos.
In the list view photos are organized in rows, each row contains the square thumbnail of a photo along with some information (i.e. number of views, likes). In this view you can scroll up or down to view more photos. To switch from thumbnails view to list view, just tap on the icon at the top right corner.
When you are in list view or thumbnails view and you tap on photo you can view the photo in details view. In Details view is where you can see information regarding the photo like comments, caption, comments, tags, location, exif, security etc. The information available in details view depends on the service where the photo is hosted. There is no details view when in Cloud File Services.
Full screen view lets you see photos using every pixel your display offers. When browsing photos either in thumbnail or list view, tap on the photo you want to see in full screen, if you are in details view you can switch to full screen with a tap on the icon on the top right corner. To hide everything around the photo, tap anywhere on the photo and the photo will be in full screen. If the quick actions toolbar is visible, you can hide it by dragging to the bottom of the screen.