Once inside a Project, you can view all boards, and all content within each board. Simply scroll to the right to access additional boards.
Click an a board's name at the top to "go into" the board. From here you can scroll to the right to access additional boards. See below:
A board’s content can be viewed in 3 ways: Card format, Post format, or Table format. These options are noted by the icons at the top right of the "opened" board:
While viewing content of a board in full-screen, you can use the Next and Previous File arrows at the top to access and view all other files within that board.