Stroke Select is a Blender addon to replace the Circle Select. You simply select elements by mouse stroke. And you can , different from the Circle select, still normally navigate meanwhile. The Circle select mode has the problem that it disables navigation. Which is a real workflow killer.

Beware Beta!

The script and further instructions can be found here: www.reinerstilesets.de/anderes/blender-addons/2016-stroke-select-addon/