IOS 10 Mail Navigation

On my iPad mini and iPad pro I no longer have navigation arrows to go forward or back between messages in an inbox. They are still there on my iPhone.

Have I missed something. It's annoying to have to go back to the inbox and select the next/previous message.

 

Perhaps this was deliberate, although I haven't been able to confirm this.

The way around the removal of the navigation arrows on iPads is to drag right and split the screen to see what in the in boxes.