Not everyone lives in America.
That includes me.
In some countries, leaving mobile data enabled causes Gogle's background activity to use all your data allowance in an hour! I have no idea why Google needs gazillions of Gigabytes in the background but it does.
That's odd. My phone (Android 4.3) only needs 3-5 MiB per day if I don't do anything special. This would then only be the traffic of receiving some e-mails and dozens of apps doing their thing. Are you taking many pictures and are using Google's auto-backup?
I think I have six. Four are obvious:
- Current work smartphone (Galaxy Nexus)
- Tablet (Sony Xperia Z2 Tablet)
- Navigation system built into car
- Portable navigation system for use in rental cars (a cheap one, don't remember the name)
Plus two more:
- Old work smartphone (BlackBerry Bold 9000) sitting in a drawer
- Navigation system built into my old car - currently used by my mother (the car but not the navigation system...)
And my wife has two more:
- Work smartphone (iPhone 5s)
- Personal smartphone (Galaxy Nexus)
More than I thought initially but not as crazy as some others here!