Board Thread:Introductions/@comment-114.198.73.236-20130723063733/@comment-4632427-20130723065622

You can expand your land from the Build menu. On the far bottom-right, there is a section called Expansion. Tap it, choose the red-bordered Land Expand, and tap Build. Then you can drag a box to any area next to your current land and tap the checkmark to start expanding there. Fair warning: each land expansion is more expensive than the one before, and they take longer and longer to complete, too.

As for tearing down unwanted buildings, tap on the Move Buildings icon - it looks like four arrows pointing away from each other. Then tap the offending building, then the dollar-sign button that appears. This lets you "sell" the building, though most buildings give tiny return, along the lines of 10 Stone and 10 Gold.