All of them are displayed in the Home tab. The little tag with a number next to a building shows you the current level of the building. When this tag has a brownish color, it means that you are currently not able to upgrade further, because you are missing certain requirements. The tag will have a green color as soon as an upgrade is possible. Each building has a special animation or an icon above it if it's active or if something can be collected from it.
All items (6)