Portable information device and cover device

A portable information device comprising:

• a first chassis;
• a second chassis adjacent to and rotatably coupled to the first chassis to enable movement between a flat plate form in which the first chassis and the second chassis are lined up with each other in a direction perpendicular to a surface normal direction and a folded form in which the first chassis and the second chassis are folded to overlap each other in the surface normal direction;
• and
• a cover device having a first cover section that covers a back surface of the first chassis, a second cover section that covers a back surface of the second chassis, and a folding cover section that rotatably connects the first cover section with the second cover section, wherein
• the cover device further has a sheet-shaped member that faces a side edge on an inner surface of the folding cover section and that is movable relative to the inner surface of the folding cover section, and
• the folding cover section covers adjacent edges of the first chassis and the second chassis in the folded form, and the sheet-shaped member covers adjacent edges inside the folding cover section as viewed from a rotating axis direction of the first chassis and the second chassis.