Shade smooth is an operation, we use very often in Blender. Most of the time, the objects we shade smooth are no rounded completely and you want to retain some sharp edges intentionally. Of course, this is what auto smooth is for, but don't you find it annoying, to go to the mesh properties and activate it there? Especially as the default angle of 30 degrees is suited for most of the cases, it would save so much time, to shade smooth with only one action. That's exactly, what the add-on does...

With the click of just one button, you can visually smooth one or more selected objects. The Button can be accessed on a prominent place at the header menu, or you use the shortcut for the action (Ctrl+Alt+S). This will automatically apply auto smooth with the default angle.

You can adjust the preset auto smooth options in the nearby add-on submenu.

Here you can activate or deactivate auto smooth of the active object and adjust the smoothing angle afterwards.

Deside, if you want to use auto smooth or just wanna utilize the button for instant toggle smooth and flat. The button always indicates, in what shading condition the object is in. 

If there are more objects selected, they all will smoothen or flatten at the same time. In case the selection contains mixed object types, you will be asked, in whether to smooth or flatten all marked objects.

The button is only available in object mode and will only work with objects which contains a mesh. 

The shortcut (Ctrl+Alt+S) for the operation and some default values can be configured in the add-on preferences. 

This add-on is by far the quickest and easiest way for your smoothing workflow.

(Let me know your wishes for further smoothing related functions and I will consider adding them…)

I hope, this makes future parts of your work easier…

Changes in Versions 

V1: Basic smooth functions

V1.1:

- Toggle Button

- Menu : Default use auto smooth, control auto smooth options

(Also have a look at my other useful products here at Blender Market...)