Basics of iPhone Status Bar Icons
The status bar runs across the very top of your iPhone in either portrait or landscape view, in apps that support landscape view. Its icons give you information about your cellular and/or wireless network connection, battery life, and auxiliary functions you may have turned on, such as Do Not Disturb and the alarm clock.
Here is an explanation of each one. Remember, you won't see them all at once on your iPhone, and some you may never see:
Airplane Mode: You see this icon if you've turned Airplane mode on in Settings.
Alarm: Appears if you set an alarm using the Clock app.
Battery: Indicates how much charge remains on the battery. It's green if the battery is between 100 and 20 percent charged. It changes to red and shows just a tiny portion on the left when less than 20 percent charge remains. It has a lightning bolt next to it when the battery is being charged.
Bluetooth: Shows that Bluetooth is turned on. When it's blue or white, you are connected to another Bluetooth device such as a headset. When it's gray, Bluetooth is on but no device is connected. You may be surprised to learn that Bluetooth is named after a Danish king.
Call Forwarding: On GSM models, appears when you've forwarded your calls to another phone number.
Cell Signal: Indicates the strength of the cellular signal your iPhone is connected to. If you have no filled-in circles or just one, the signal is weak — more solid circles, stronger signal. No Service appears when iPhone is unable to pick-up a signal from your cellular provider. If Airplane Mode is turned on, you see the airplane icon instead of the cell signal circles.
Do Not Disturb: Reminds you that you have activated the Do Not Disturb feature.
EDGE (E): Appears when iPhone is connected to your cellular provider's EDGE data network for accessing the Internet. GSM models support EDGE networks.
GPRS/1xRTT: GSM models use the GPRS (General Packet Radio Service) network and CDMA models use the 1xRTT (1x Radio Transmission Technology) network to access the Internet when those networks are available.
Location Services: When you see this icon, an app, such as Maps or Reminders, is tracking your current location coordinates in order to provide you with nearby information or other services.
LTE: Lets you know you have an LTE cellular connection; this icon may be 4G, depending on your carrier.
Network Activity: Spins when iPhone is accessing a cellular or Wi-Fi network for any app that uses the Internet, such as Safari or the App Store. It also appears when iPhone is syncing iCloud information over-the-air, or sometimes when an app is performing other data-related activities.
Personal Hotspot: This icon is active when you've connected to another iPhone or a 3G/4G iPad that is providing a Personal Hotspot.
Orientation Lock: This reminds you that you've turned off the landscape view feature. You can turn your iPhone every which way, but the screen remains in portrait position — unless you open an app that only works in landscape position, such as some games or videos.
Syncing: Indicates that your iPhone is syncing with iTunes or iCloud.
TTY: Indicates your iPhone is configured to work with a Teletype (TTY) machine.
UMTS/EV-DO (3G): Indicates when GSM models are connected to the UMTS (Universal Mobile Telecommunications System) network, or CDMA models are connected to the EV-DO (Evolution-Data Optimized) network to access the Internet when those networks are available.
VPN: Indicates iPhone is connected to a VPN (Virtual Private Network).
Wi-Fi: Indicates iPhone is connected to a Wi-Fi network. The more bars, the merrier, the more stable — the connection.