The free version of Trivice for the calculation of any given triangle.The necessary parameters are:- Three sides or- Two sides and one angle or- One side and two anglesThe input is done completely without the keypad by using the graphical controllers on the edges and sides. The value of the active controller is displayed in the middle.The commercial versions Trivice and Trivice HD can additionally calculate the area, height, perimeter, incircle and circumcircle. They also offer a graphical rendering of the result and a history to recall the most recent calculations.