This is some pretty heavy-duty obfuscation. What is the business case for this amount of work towards preventing reverse-engineering? Decent rate limiting should be much more effective than making such a herculean effort to obfuscate one's API.

Edit: another comment mentions that snap chat uses an existing solution, which makes more sense than the expense of developing this sort of obfuscation in-house: https://news.ycombinator.com/item?id=23558784