Why I built it
A big screen, already in my pocket.
iPhone Duo opens into a big screen. I wanted it next to my laptop as a second display, so I built this.
Nils
Sidekick DisplayYour iPhone Duo as a second screen for Mac and Windows
Turn your phone into a second screen.
Plug in your iPhone Duo and your Mac or PC gets a big screen you can touch.
- Works with Mac and Windows
- Tap, drag and scroll with touch
- Fold it and the display follows
Download on theApp StoreDownload forMacDownload forWindowsFree to try. macOS 14+ and Windows 10 or 11 (beta).
Why it's different
Follows the fold
Open it for the big screen, fold it for the cover screen. Your Mac rearranges itself.
Wired and fast
USB with hardware video encoding, for low lag.
Private
No account, no analytics. Nothing leaves your desk.
Touch control
Tap to click, drag to move, two fingers to scroll, hold to right-click.
Extend or mirror
Keep chat or music on your iPhone, or show exactly what's on your Mac. Swipe down for controls.
Larger text or more space
Pick true-to-life text, or a size that fits more of your Mac on the Duo's screen.
Everything else
Plug in and go
Connect a cable and the display starts by itself.
Mac and Windows
Extend or mirror your Mac. On Windows 10 and 11, mirror your PC's main screen (beta).
Sidekick Display Pro
60 fps, every display size, Wi-Fi and unlimited time. The free plan runs at 30 fps for 20 minutes a day.
Questions
Do I need an app on my computer?
Yes. Sidekick Display for Mac (macOS 14 or later) and for Windows (Windows 10 or 11) are free downloads from this page.
Does it work with Windows?
Yes, in beta. Your iPhone shows a copy of your PC's main screen, with touch. For USB, install Apple's free Apple Devices app from the Microsoft Store. Extending your desktop, like on a Mac, is coming.
Does it work on other iPhones?
Yes, any iPhone on iOS 17 or later. It's made for iPhone Duo, where it uses both screens.
Why does the Mac app ask for permissions?
Screen Recording sends the picture. Accessibility turns your touches into clicks.
Is it free?
Yes, at 30 fps for 20 minutes a day. Pro removes the limits.
Does it work over Wi-Fi?
Yes, with Pro. USB gives the lowest lag.
Sidekick Display
Your iPhone Duo as a second screen for Mac and Windows.
Download on theApp StoreDownload forMacDownload forWindowsFree to try. macOS 14+ and Windows 10 or 11 (beta).
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