In recent years, different optimization problems have been arose in the context of UI design. Initially those problems were solved by hand with no computational optimization support since the set of potential design combinations was limited. However, when the space of different possible designs increase, the use of optimization algorithms is mandatory. However, several UI design problems are quadratic, for which guaranteeing the global optimum is not possible in polynomial time. Then the use of classic exact methods may not be feasible. In this paper, we briefly present how metaheuristics can straightforwardly be used to model and solve interesting but complex quadratic problems from UI design. In particular, we employ Cuckoo Search, which is a modern optimization technique to solve a well-known problem concerned to keyboard layout optimization.