Mini-Spectrometer... how to build

In this post you can find the links to create this foldable mini-spectrometer.
Here is the video with the steps to create one:

And here is my first picture that I took with my smartphone:

Mini-Spectrometer

In a earlier post, I published how to build a spectrometer with house stuff. Now, a Physics teacher (friend of mine) show me this great website that show us how to build a mini-spectrometer. You can attach to an smartphone, laptop, or computer with a camera and submit your image to http://spectralworkbench.org/ (point your browser to the website and click "capture").