General and system

Background App Refresh lets apps fetch new content while they are closed, which keeps them current at the cost of battery and data.

Settings > General > Background App Refresh

The Software Update screen shows which iOS version you have, offers any update that is available, and holds the automatic update settings.

Settings > General > Software Update

This screen breaks down what is using your storage, app by app, and offers specific recommendations for freeing space.

Settings > General > iPhone Storage

This forgets every Wi-Fi network and password, resets cellular preferences and VPN settings, and leaves the rest of your phone untouched.

Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings

You can allow iOS to download updates automatically, install them automatically, or both, with installation happening overnight while charging.

Settings > General > Software Update > Automatic Updates

This sets the system language, the region used for formatting dates, times, numbers and currency, and the measurement system.

Settings > General > Language & Region

This sets whether the clock updates automatically from the network, which time zone you are in, and whether time is shown in 24 hour format.

Settings > General > Date & Time

Every preference returns to its default value while your apps, photos and messages stay exactly where they are.

Settings > General > Transfer or Reset iPhone > Reset > Reset All Settings

Video and FaceTime calls can shrink into a floating window when you leave the app, so playback continues while you do something else.

Settings > General > Picture in Picture

A configuration profile can change settings, install certificates, add VPNs and restrict features, and this screen shows every one installed.

Settings > General > VPN & Device Management

This clears every word the keyboard has learned from your typing, so autocorrect starts again from scratch.

Settings > General > Transfer or Reset iPhone > Reset > Reset Keyboard Dictionary