Repeating changes with Transform again in Vectornation
Transform again and Transform each in Vectornation by Zaweba repeat a transform or apply one to every object on its own, for patterns and tidy sets.

Two commands in Object, Transform look modest but save a great deal of repetitive work. Transform again repeats the last transform. Transform each applies a transform to every selected object separately rather than to the selection as a whole. Both are part of Vectornation by Zaweba, and they solve different problems.
Transform again
Transform again repeats a transform. Make a change, such as moving a copy a set distance or rotating a copy by an angle, then call Transform again and the same change happens once more. Keep calling it and the change keeps repeating.
The classic use is building a row or ring of copies. Move a copy of an object across by a set amount, then Transform again several times and you have an evenly spaced row. Rotate a copy around a centre by an angle, then repeat, and you have a ring. The spacing is exact because it is the same change every time.
It works with any transform: a move, a scale, a rotation or a combination. Repeating a slightly smaller, slightly rotated copy makes a spiral of shapes, a pleasing effect for backgrounds and decorative art.
Transform each
Transform each applies a transform to every object separately. Select several objects and transform them, and each changes around its own centre instead of the whole group changing around one point.
The difference is easy to see with rotation. Rotate a row of squares as a selection and the whole row tilts like a plank. Rotate each and every square turns where it stands, and the row stays straight. The same goes for scaling: scale a set of icons as a selection and they move closer together or further apart; scale each and they grow or shrink in place.
Jobs they help with
Patterns are the natural home of Transform again. Rows of dots, rings of numbers on a dial, stripes, spirals and repeated motifs all come quickly from one transform repeated.
Transform each helps with sets of things that should change together but stay put. Resizing a set of buttons, turning all the arrows in a diagram by a quarter turn, or adding a slight random looking tilt to scattered elements are all clean with it.
Combining with other tools
The Transform tool has repeat and transform each options in its options bar, so you can work the same way from there. Step and repeat makes rows by columns of copies with gaps, which suits grids for print. The Repeater tool and live repeats under Object, Repeat keep repeated designs editable, which suits patterns you expect to change.
Choose by how settled the design is. For a quick, fixed set of copies, Transform again is fastest. For a pattern you may adjust later, a live repeat is better because you can change the original and the copies follow.
Pitfalls
Transform again repeats the last transform, so make sure nothing else has happened in between. If you nudge something else, the command will repeat the nudge.
With radial copies, choose an angle that divides evenly into a full turn so the last copy meets the first neatly.
With Transform each, think about whether you want objects to change in place or as a group. If the row should tilt as a whole, the ordinary transform is right.
Two small commands, then, but used well they turn many minutes of copying and adjusting into a few keystrokes in Vectornation by Zaweba.