As a Samsung galaxy s2 sgh-t989d Hercules user, I can tell you there's only two possibilities:someone modding the app to work on older OS's(unlikely and will be behind updates), or by flashing a custom ROM like cyanogen. I won't go into how to do that here, but if you don't understand the instructions you find on Google don't do it, you could brick your phone. I spent a good 4-5 hours last Sunday rooting, using Odin, crawling CyanogenMod forums, and installing outdated firmware with an outdated bootloader to eventually get CyanogenMod 11, which supports the minimum 4.4 kitkat OS.
EDIT: There's also a chance that your phone hasn't auto updated, head into your phone's settings, scroll to the bottom and check out the about tab, should be some options for updating your os in there if it's possible.