On Wed, 25 Mar 2015 at 12:53 Rohan McLeod <rhn@jeack.com.au> wrote:

Regarding: "you should be able to disable the pre-installed apps using
settings -> Apps -> All -> (select app) -> Disable."
closest gui path I can see to this is: Apps>Settings>Application
Manager>All> no sign of (select app)

Best I can think of is that app name isn't what you are expecting it to be. Which could make it hard to find in the list.

but I notice : >Android System tells me "version 4.1.2-19100TDVLSM";
where as
http://www.samsung.com/uk/consumer/mobile-devices/smartphones/android/GT-I9100LKAXEU

states the android version seems to be "Android 2.3 (Gingerbread) "
Not sure what to make of that; since what I know of the previous owner
suggests OS upgrade would be unlikely !

The version the phone gives is the authoritative source, chances are the website hasn't been updated in ages. Also updates typically happen over the air (eventually with Samsung when they decide to actually provide an upgrade) so all the previous owner would have had to do is click "yes" when prompted to do the upgrade.