The icons in the status bar at the top of the screen give information about iPhone:


Status icon

What it means
the cellular signal strength status icon (five dots)
Cell signal
You’re in range of the cellular network and can make and receive calls. If there’s no signal, “No service” appears.
the Airplane mode status icon
Airplane mode
Airplane mode is on—you can’t make phone calls, and other wireless functions may be disabled.
the LTE status icon
LTE
LTE network is available, and iPhone can connect to the Internet over that network. (iPhone 5 and later. Not available in all areas.)
the 4G status icon
UMTS
Your carrier’s 4G UMTS (GSM) or LTE network (depending on carrier) is available, and iPhone can connect to the Internet over that network. (Not available in all areas.)
the 3G status icon
UMTS/EV-DO
Your carrier’s 3G UMTS (GSM) or EV-DO (CDMA) network is available, and iPhone can connect to the Internet over that network.
the EDGE status icon (an “E”)
EDGE
Your carrier’s EDGE (GSM) network is available, and iPhone can connect to the Internet over that network.
the GPRS status icon
GPRS/1xRTT
Your carrier’s GPRS (GSM) or 1xRTT (CDMA) network is available, and iPhone can connect to the Internet over that network.
the Wi-Fi call status icon
Wi-Fi call
iPhone is set up for Wi-Fi calling. iPhone also displays a carrier name next to the icon. .
the Wi-Fi status icon
Wi-Fi
iPhone is connected to the Internet over a Wi-Fi network.
the Do Not Disturb status icon
Do Not Disturb
“Do Not Disturb” is turned on.
the Personal Hotspot status icon
Personal Hotspot
iPhone is providing a Personal Hotspot for another device.
the syncing status icon
Syncing
iPhone is syncing with iTunes.
the network activity status icon
Network activity
Shows that there’s network activity. Some third-party apps may also use it to show an active process.
the call forwarding status icon
Call Forwarding
Call Forwarding is set up.
the VPN status icon
VPN
You’re connected to a network using VPN.
the TTY status icon
TTY
iPhone is set to work with a TTY machine.
the portrait orientation lock status icon
Portrait orientation lock
The iPhone screen is locked in portrait orientation.
the alarm status icon
Alarm
An alarm is set.
the Location Services status icon
Location Services
An item is using Location Services.
the Bluetooth status icon
Bluetooth®
Blue or white icon: Bluetooth is on and paired with a device.
Gray icon: Bluetooth is on. If iPhone is paired with a device, the device may be out of range or turned off.
No icon: Bluetooth is turned off.

the Bluetooth battery status icon
Bluetooth battery
Shows the battery level of a paired Bluetooth device.
the battery status icon
Battery
Gray icon: Shows the iPhone battery level or charging status.
Yellow icon: Low Power Mode is on.