Chrome vs iOS 9 performance over Slow 3G connection

I am testing a site for performance over slow 3G speeds. Compared to Chrome, the results consistently show very long loading times in iOS 9. The difference is a lot, 30s give or take.

Dulles, VA - iPhone 5c iOS 9 - 3GSlow:
https://www.webpagetest.org/result/170602_SB_P8K/

Dulles, VA - Galaxy S5 - Chrome - 3GSlow:
http://www.webpagetest.org/result/170602_G4_N9T/

Any help as to what this might be?

Disclaimer: I am not the most technically savvy person, so please be gentle. :shy: