Actually, the mosque is same in Sunni and Shiite. The prayers are also same; there may be small differences in the body movements in prayers, but more than those differences exist in among Sunni mazhabs.
The difference between Shiite and Sunni is not in the shape of Mosque, or in the practice of prayers. I don't say that there are no differences, there are some small differences but these differences are not a completely related to being Sunni or Shiite.
One of my friends from University was Shiite, am neither Shiite or Sunni, and we were having our prayers in a Sunni Mosque. There was nothing strange for us, it was all natural.
EDIT: About prayer times in a day.
Siites also pray 5 times a day like Sunnis do, but they shorten it to 3 times when they are busy in the day.