From Tiny Tower Wiki
The Lobby is a drab purple striped room devoid of any bitizens. The floor is made of orange brick tiling, and to the left of the door is a desk with a solitary computer monitor and what is probably the side of a yellow spinning chair behind it. Three identical lights illuminate the desk, with a stainless steel wall behind them. To the right of the door is a sign displaying the floors of the tower, and three yellow bushes in large clay pots sit in front of two large windows.
The Lobby has no stock, no residents and no available upgrades. It cannot be moved, although it can be painted like any other floor. The Lobby has no real use except to serve as the main level of your Tiny Tower. No Bitizens are ever seen in the lobby, although Bitizens do wait outside of the elevator on the Lobby's level.