Right here. It used to be to the left of the wifi button back with 4.2. It was taken away with 4.3 and still gone with 4.4.2 .
It's not that big of a deal, but it was really handy and quick to be able to just pull down the notification menu and click it on or off as needed.
http://img.tapatalk.com/d/14/03/14/ubusy7ep.jpg
http://img.tapatalk.com/d/14/03/14/uzumyga8.jpg
Like I said above it was just nice and quick like that, but from 4.3 on, you have to pull down the notification menu, click settings, click data usage and turn it on or off in there with the check mark.
Like this screen shot I just took as well.
http://img.tapatalk.com/d/14/03/14/ade2aqyr.jpg
Doing stuff faster is how I liked it. Oh well I've learned to live with it like this, not a huge deal, just annoying that we can't customize to our liking. Can't please us all I guess.
But other then that, so far so good, I didn't like 4.3 much at all. This 4.4.2 is WAY more smooth and quicker doing stuff. All around as of now I like it alot better than previous updates.
No problems with my SD card functions as well. (64gig class 10)
Not sure as of now, the battery life compared to before is better, worse or the same, only time will tell me that I guess. But seems fine so far.
Also freed up a half gig of space or more on the phone as well. Not bad not bad......
Hope that helped.
Sent from my shed.