Night mode on iPhone is primarily a camera feature that automatically activates in low-light conditions, and you can control or adjust it directly in the Camera app when needed. Here’s how to access and use it depending on your iPhone model and iOS version: What night mode does

• Night mode automatically detects low-light scenes and increases exposure time to improve detail and reduce noise in photos. You’ll see a moon icon with a yellow indicator when night mode is available and active. [type:web:index]
• You can manually enable or adjust night mode from within the Camera app if lighting conditions trigger it or if you want to override automatic behavior. [type:web:index]

How to use Night mode in the Camera app

• Open the Camera app in Photo (and, on some models, Portrait) mode. If lighting is low, the night mode icon (a moon) appears near the top-left or near the shutter button, depending on iOS version. Tap the icon to enable or disable Night mode, and use the slider to set the exposure duration (Longer times for more light). [type:web:index]
• If you don’t see the night mode option, your current lighting or camera mode might not support manual Night mode on that device. Night mode is available on iPhone models starting with iPhone 11, with more advanced control on newer models. [type:web:index]

Automatic activation and tips

• Night mode turns on automatically when the camera detects insufficient light, and it may be off in very bright scenes. You can still force it on by tapping the Night mode icon in the camera app. [type:web:index]
• For best results, keep your iPhone steady during the capture, or use a tripod. In darker environments, you may want to increase the exposure time by sliding the Night mode duration toward Max. [type:web:index]

Preserving camera settings (optional)

• Some iOS versions offer a Preserve Settings option for the camera, which can keep your Night mode choice across launches if you prefer to stay in or out of Night mode by default. Check in Settings > Camera > Preserve Settings if you want Night mode to remain off or on when you reopen the app. [type:web:index]

Model-specific notes

• Night mode availability and controls vary by iPhone model and iOS version. If you have an iPhone 11 or later, you’ll generally have Night mode in the camera, with more precise control on newer devices. If you’re using an older model, Night mode may be automatic or not available. [type:web:index]

If you’d like, tell me your iPhone model and iOS version, and I can give you the exact steps for your device. [type:web:index]