This app is intended for persons with an interest in Einsteins Special Theory of Relativity. The interested party, or student, may wish to easily access the results of basic calculations. It is not a didactic treatment of the Special Theory. Students of the theory may find benefit as a check on their understanding. Two types of calculations are available. The first type is for the Lorentz contraction, expansion, and dilation effects wherein the physical parameters of length, mass, and time lapse are viewed between frames undergoing relative motion. The second type is for the Lorentz transformation of the space-time 4 vector components for the same type of inertial frames relative motions.