The transform tool is an all-in-one tool used to reposition, reorient, and resize parts in Studio. It is designed to supplement the other transformation tools (i.e. Move, Scale, and Rotate).
To move a part with the transform tool click and drag on the part. This will move the part along the Selected Plane. Dragging on the yellow arrow will move the part up and down relative to the selected plane.
To scale a part with the transform tool drag on one of the square handles on the corners or edge of the selected part. This will resize the part along that axis (or in two axes if dragging on the corner).
To rotate a part with the transform tool drag on one of the arrow handles around the edge of the part. This will rotate the part about that axis. While dragging a circle with tick marks will appear. Dragging on the inside of the circle will rotate by 22.5 degrees, dragging on the outside of the circle will rotate by 1 degree.
To change the plane that parts are dragged along with the transform tool, click on the plane selector in the upper left hand corner of the workspace. Then click on the face of a part you want to use as the dragging plane. While hovering over a part in this mode you will see both the plane that will be selected if you click (highlighted in blue), and the origin of the plane (represented by a yellow cursor). The origin determines the 0,0,0 coordinate of the new plane.
If a part is rotated relative to a plane, it can be snapped to the plane by shift clicking on the part while the part is selected with the transform tool.