From time to time you will be hearing advices that if a person wants to be good, first he/she needs to imitate, copy or learn from other good examples. Yup, this is actually a very practical example. You need to learn from others in order to discover and establish your own creation.
This applies to the world of coding too. And recently, I stumbled upon this learning website Code4Startup from Product Hunt that you can learn to code with front-end and back-end technologies by cloning popular real life startup projects.