How to Use Spantop

When you first launch Spantop, you'll see the welcome screen. It gives you a quick overview of what Spantop does — extend your display using any Android tablet or Mac, connect via USB-C or WiFi, and interact with full touch and mouse input. Tap "Get Started" to begin the setup process.

Spantop needs Screen Recording permission to capture your virtual display and stream it to your connected device. Click "Grant Screen Recording" — this will open the macOS System Settings to the Screen Recording section. Toggle the switch next to Spantop to enable it.

macOS will open System Settings → Privacy & Security → Screen & System Audio Recording. Find Spantop in the list and toggle it on. Once enabled, the setup wizard will automatically detect the permission and move you to the next step — Accessibility.

Accessibility permission is required to forward mouse and touch input from your connected device to the virtual display. Click "Grant Accessibility" and toggle Spantop on in System Settings → Privacy & Security → Accessibility. After granting both permissions, the wizard shows a device setup screen where you choose what to connect — an Android Tablet or Another Mac.

After permissions are granted, Spantop asks what you'd like to connect. You have two options: Android Tablet or Another Mac. You can always connect more devices later. The screen also shows connection tips — Wired (USB 3.x / Thunderbolt) gives the best quality, while WiFi requires both devices to be on the same network. Click "Quit Spantop" to finish setup — you need to reopen the app from Applications for the permissions to take effect.

If you select "Android Tablet", Spantop shows three setup steps: (1) Download Spantop on your tablet from the Play Store. (2) Enable USB Debugging on your tablet by going to Settings → About → tap Build Number 7 times → go to Developer Options → enable USB Debugging. (3) Connect your tablet via USB-C cable and tap Connect on both devices.

If you select "Another Mac", Spantop shows two steps: (1) Install Spantop on the other Mac. (2) Switch to Receive mode — open Spantop on the other Mac and click the "Receive" tab in the menu bar dropdown. A helpful screenshot is shown so you know exactly what to look for. Both Macs need to be on the same WiFi network, or connected via USB-C / Thunderbolt cable.

After setup, Spantop lives in your Mac's menu bar. Click the Spantop icon to open the dropdown. You'll see the Share/Receive mode toggle at the top. In Share mode, you'll see a "Get Started" guide with instructions for both Android Tablet and Another Mac connections. At the bottom, click "Scan for Devices" to find available devices on your network or USB. You also have quick access to Settings, About, and Quit.

Once Spantop discovers a device (in this case, "Devanshi's MacBook Air" over WiFi), it appears in the device list with a green indicator showing it's available. The connection type (WiFi) is shown beneath the device name. Click on the device to connect and start extending your display.

Select the discovered device and click "Add Device" to initiate the connection. Spantop will create a virtual display on your Mac and start streaming it to the connected device. The "Scanning for devices..." indicator shows that Spantop is continuously looking for new devices you can connect. You can connect multiple devices simultaneously — each becomes an independent display.

Switch to the "Receive" tab to use this Mac as a second display for another Mac running Spantop. In Receive mode, your Mac advertises itself on the network (shown as "Advertising as Aditya's MacBook Air (2)"). The sender Mac will discover this device automatically. Once the sender connects, your screen will display the extended desktop with full mouse and keyboard input forwarding.