v6:
Physical Apparatus needed to use App
A diffraction grating to be place in front of the camera
Light source such as a multi propose laser pointer
Handphone with App/Chrome Browser or a laptop with camera

recoded to work better now
added back camera
added calibration of known zeroth and first order diffraction light of RED laser.
added auto find light

current version 4
some phones/Android OS (XiaoMi etc) may require App permission for CAMERA to be turn on.
some phones/Android OS (Samsung) could be automatic.
close the App and restart App again it should now detect the given CAMERA permission.




About
An open source physics at Singapore simulation based on codes written by Félix Jesús Garcia Clemente.
more resources can be found here
http://iwant2study.org/ospsg/index.php/interactive-resources/physics

Introduction
prototype

Interesting Fact
This data logger record intensity of brightness of red greenblue light and even allows the phone camera to record real time data.

Acknowledgement
My sincere gratitude for the tireless contributions of Francisco Esquembre Fu-Kwun Hwang Wolfgang Christian Félix Jesús Garcia Clemente Anne Cox Andrew Duffy Todd Timberlake and many more in the Open Source Physics community. I have designed much of the above based on their ideas and insights.
This research is supported by the eduLab project AEP 01/18 LTK Promoting joy of learning by turning phone into 3 scientific equipment awarded by the Ministry of Education (MOE) Singapore and managed by National Institute of Education (NIE) Singapore.
reference:
http://iwant2study.org/ospsg/index.php/projects/576-aep-01-18-ltk-promoting-joy-of-learning-by-turning-phone-into-3-scientific-equipment