First, Sidecar is for a Mac
Apple's Sidecar extends or mirrors a Mac onto an iPad, over Wi-Fi or a cable. It needs a Mac with macOS Catalina or later, so it does not work with a Windows PC. Windows has no built-in way to use an iPad as a screen either, so each option below runs an app on the PC. On the iPad, most use their own app; Deskreen uses the web browser. Source: Apple Support.
The options
Prices and plans change. Follow each source for the current terms.
EternalMonitor, by Sideband Studio
- Price
- Free, with no account.
- Open source
- Yes, MIT license.
- Connection
- Wi-Fi or USB cable. Plugging in the cable takes over a running Wi-Fi session.
- Extend or mirror
- Both.
- Pencil pressure
- Yes, with tilt, as Windows Ink. Drawing mode ignores your palm on the canvas.
- Needs
- Windows 10 version 1809 or later, or Windows 11, 64-bit. iPadOS 17 or later.
Duet Display, by Duet, Inc.
- Price
- Paid plans, billed monthly or yearly, or a one-time lifetime purchase. A 7-day free trial. Duet Starter is wired only; Duet Air adds wireless.
- Open source
- Not stated.
- Connection
- USB cable, or wireless with Duet Air and higher plans.
- Extend or mirror
- Both.
- Pencil pressure
- Pressure and tilt with Duet Pro, says its App Store listing.
- Needs
- Windows 10 or later.
spacedesk, by datronicsoft
- Price
- Free for private, non-commercial use. Commercial use needs a paid license, bought in the app.
- Open source
- No. Source code is licensed only to system integrators.
- Connection
- Wi-Fi, network cable or USB. The iPad app lists USB or a local network.
- Extend or mirror
- Both.
- Pencil pressure
- Yes, in the iPad app with Pen input turned on, says spacedesk support.
- Needs
- Windows 10 or 11.
Splashtop Wired XDisplay, by Splashtop
- Price
- The iPad app is listed as free. The computer agent is a free download.
- Open source
- Not stated.
- Connection
- USB cable only, Lightning or 30-pin in its listing.
- Extend or mirror
- Both, by its name.
- Pencil pressure
- Not stated.
- Needs
- Windows 7 or later. The iPad app was last updated in August 2017.
Twomon SE, by DEVGURU (Easy&Light)
- Price
- $9.99 for the iPad app in the US App Store. The PC program is free.
- Open source
- Not stated.
- Connection
- USB cable.
- Extend or mirror
- Extend. Mirror is not stated.
- Pencil pressure
- Not stated. It lists touch.
- Needs
- Windows 10 version 1703 or later.
Luna Display, by Astropad
- Price
- $89.99, one time, for a small adapter that plugs into the PC's USB-C or HDMI port. No subscription.
- Open source
- Not stated.
- Connection
- Wi-Fi or USB cable. The adapter must plug straight into the PC.
- Extend or mirror
- Extend. Mirror is not stated.
- Pencil pressure
- Not stated for Windows. Its listing says it supports Apple Pencil.
- Needs
- Windows 10 64-bit, build 1809 or later.
Any Display, by FULLSTACKHUB
- Price
- Free to download with a free trial. A one-time purchase includes a year of updates; more updates are a paid extension.
- Open source
- Not stated.
- Connection
- Wi-Fi or USB cable.
- Extend or mirror
- Both. Mirror can show one app window.
- Pencil pressure
- Pressure and tilt, sent to Mac and Windows apps.
- Needs
- Windows 10 or 11, 64-bit. iPadOS 16 or later.
Deskreen, by Pavlo Buidenkov
- Price
- Free. The site also offers a paid Pro plan.
- Open source
- Yes, AGPL-3.0.
- Connection
- Wi-Fi. The iPad views it in a web browser, with no app to install.
- Extend or mirror
- Mirror. Extending needs a virtual display adapter as well.
- Pencil pressure
- Not stated.
- Needs
- Runs on Windows, macOS and Linux.
Who EternalMonitor suits
Anyone with a Windows PC and an iPad who wants a second screen or a drawing tablet without paying for one.
- Free and open source. MIT license, no account, and code you can read.
- Your graphics card does the work. On supported graphics, NVIDIA NVENC, AMD AMF or Intel Quick Sync encode H.264 or HEVC at 30, 60, 90 or 120 fps, with 120 on iPads with ProMotion.
- Wi-Fi or USB. A cable takes over a running Wi-Fi session and can charge the iPad from a USB-C port. Unplug it and the stream goes back to Wi-Fi.
- Apple Pencil as a real pen. Windows receives pressure and tilt as Windows Ink, and Drawing mode ignores your palm on the canvas.
- Loss repair for real Wi-Fi. The iPad asks again for a missing packet right away, so one dropped packet rarely costs a frame.
- PC audio. Sound plays on the iPad, and you can mute it without stopping the video.
- Updates in one click. On Windows, Update now checks the download and installs it.
The compatibility page has the measured results.
Try it
The step-by-step guide takes about 10 minutes. If a fact on this page is wrong or out of date, tell us and we'll fix it.