Google ANDROID Quick Start Guide (4.4, KitKat) - Manual (Page 20)

ANDROID QUICK START GUIDE ESSENTIALS 16
Bluetooth, Wi-Fi,
mobile network &
battery status
Pending
notifications
TIP: Wi-Fi and mobile signal strength are indicated at
the top of the screen by white bars. To see whether the
selected Wi-Fi network has a full Internet connection,
open Quick Settings: swipe down from the top right on
tablets or with two fingers on phones.
In Quick Settings only, white bars in the Wi-Fi or
mobile signal indicators indicate the signal strength
of a normal Internet connection, while
orange bars
indicate that some web services may not be functioning
normally. For example, sometimes the mobile signal bars
turn orange briefly when you turn on your device, until a
full connection is established.
Also in Quick Settings only, you may notice small up or
down arrows just to the right of the Wi-Fi or mobile signal
indicators. The up arrow indicates data streaming from
your device to the Internet and the down arrow data
streaming from the Internet to your device.