I would suggest that you ask KevinSystrom and/or Mike Krieger for
a couple of copies of their very comprehensive construction manual.
Then, starting at the beginning, you and your colleague(s) should
work your way, with the utmost diligence, to the very last page.
Voilà, you will then have created a clone, just give it another name
like "Jiffygram" for example and you're ready to go.