Check with http://caniuse.com/#search=transforms and see if the CSS transform is supported on that OS build. I don't think that version of iOS supported it.
You might want to look at the Crosswalk project and see if that solution might work.
Perhaps you could try prefixing transform in the prefixed -webkit-transition?
-webkit-transition: transform 2s;
-webkit-transition: -webkit-transform 2s;
If that doesn't work, maybe try 'all' to see if it's something else?
-webkit-transition: all 2s;
transition: all 2s;
-webkit-transform worked a treat.
Thanks very much