Regulator is the missing layout and transform manipulation tools for Unity. It gives you complete control over precise or randomized adjustments, alignment and distribution of any set of Transforms or RectTransforms, in any space, with any hierarchy. Regulator unifies 2D and 3D transform changes into a single system, using common terms and operations.
Use it to align and distribute UI elements, to arrange objects in levels, to average x positions, or to nudge everything in the scene by 1 world unit up.
It was designed for seamless, transparent use, like a sidekick that can handle anything behind the scenes for you. Once configured, you can apply your absolute and relative adjustments to changing selections with a keyboard shortcut. It includes an API for doing the same manipulations at runtime.
It will soon become indispensable to you, just as Unity has.
Usage Docs
API Docs