Below you can see the front-view size comparison of the Olympus TG-4 and Olympus E-M10 II. The Olympus TG-4 is clearly the smaller of the two cameras. Its body is 8mm narrower, 17 mm shorter and 16 mm thinner than the Olympus E-M10 II.
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.