Clamshell Mode

Clamshell mode lets you run your MacBook with the lid closed, using your Daylight or Android device as the primary display over USB. SuperMirror handles the virtual display and streaming automatically.

Requirements

MacBook plugged into power (required — macOS sleeps on lid-close without it)
USB cable connecting Mac to your Android device
SuperMirror running and mirroring started before closing the lid
A Bluetooth keyboard and mouse, or the device's on-screen keyboard

Setup

Connect your Mac to power.
Connect your Android device via USB.
Open SuperMirror and start mirroring (menu bar → Start Mirror, or press Ctrl+F8).
Confirm the stream is visible on your device before closing the lid.
Close the MacBook lid. macOS will stay awake because it's on power with an active display.

macOS requires power to stay awake in clamshell mode. If your Mac sleeps after closing the lid, check that it's plugged in.

Keeping the display awake

SuperMirror creates a virtual display that macOS treats as a real external monitor. As long as mirroring is active and the Mac is on power, the system will not sleep when you close the lid.

If you find the Mac sleeps anyway, check System Settings → Battery → Options and ensure "Prevent automatic sleeping on power adapter when the display is off" is enabled.

Waking from sleep in clamshell

If your Mac does sleep while in clamshell, you can wake it with a Bluetooth keyboard key press or by briefly re-opening the lid and pressing a key. Once awake, SuperMirror will reconnect automatically — the Android app will show "Reconnecting..." and then resume streaming within a second.

Hotkeys in clamshell

All SuperMirror keyboard shortcuts work normally in clamshell mode. Use a Bluetooth keyboard connected to your Mac:

Ctrl+F8 — toggle mirroring on/off
Ctrl+F1 / Ctrl+F2 — decrease/increase brightness
Ctrl+F3 / Ctrl+F4 — decrease/increase warmth

Resolution in clamshell

SuperMirror sets the virtual display resolution to match your device's screen. This is the same resolution used when mirroring with the lid open. You can adjust it from the menu bar if needed.

Troubleshooting

Mac sleeps when lid is closed

Make sure the Mac is connected to power. macOS won't stay awake in clamshell mode on battery.

Display shows black screen after closing lid

Some Macs briefly flicker or pause when switching display configurations. Wait 2–3 seconds — the Android app will reconnect automatically.

Mirroring stops after closing lid

This usually means the Mac went to sleep. Check power connection and the sleep setting in System Settings → Battery → Options.

See the troubleshooting guide for more help.