SizeWell 0.8 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The most popular version of the program is 0.8. The bundle identifier for this app is com.randomapplications.sizewellinstaller.
The software is also known as "SizeWell Installer". The actual developer of this free software for Mac is Random Applications. This free program is compatible with Mac OS X 10.5 or later. We recommend checking the downloaded files with any free antivirus. The application lies within Design & Photo Tools, more precisely Viewers & Editors.
From the developer:
While resizing a window, hold a customizable modifier key to keep width/height, aspect ratio, centered, or to pin bottom right corner.
When zooming a window, hold a customizable modifier key to maximize whole screen or to any half. Undo a zoom by performing the same zoom feature again before doing anything else to the windows size or position.
You may want to check out more Mac applications, such as Smith Chart for Mac, Movie2Shot or TVPaint Animation, which might be similar to SizeWell.