SideMiniComparison
Sidecar vs Luna Display vs Duet Display for a Mac mini
There are three serious ways to make an iPad the screen of a Mac mini, and they are not interchangeable. One is free and built in, one is a hardware dongle, one is a subscription app. This is an honest comparison, including where our own app fits and where it does not.
Sidecar
Apple’s own feature, on every supported Mac and iPad since 2019. Excellent latency, HiDPI, Apple Pencil, USB or wireless, zero cost. Its limits are the ones Apple designed in: a person must start it from a real screen, it forgets after restarts and sleeps, and it cannot connect to a Mac that has no display at all.
Where it wins: picture quality, price, no third-party drivers. Where it loses: automation and headless use.
Luna Display
A small USB‑C or HDMI dongle from Astropad, around $130 at the time of writing. It presents itself to the Mac as a real display, so headless Mac minis work by design, and the companion app streams that display to an iPad or even another Mac or PC. Its “Mac-to-Mac” and headless modes are genuinely good.
Where it wins: hardware-grade headless support, cross-platform. Where it loses: price, one more thing to carry and lose, a client app on the iPad, and it still needs the Mac to reach the desktop on its own.
Duet Display
A long-running app that turns iPads, Android tablets and other computers into displays, wired or wireless, on a yearly subscription, roughly $25–40 per year depending on tier. Works with Windows too. On Macs it installs its own display driver.
Where it wins: platform breadth. Where it loses: recurring cost, a driver on the Mac, and image quality and latency that Sidecar generally beats on Apple-only setups.
SideMini (Sidecar, automated)
SideMini is not a display technology. It is a menu bar app that makes Sidecar do the two things it will not do by itself: start at login without a person clicking, and work on a Mac with no monitor, by creating a virtual display first. You keep Sidecar’s picture and Pencil support. It is a one-time purchase with a three-day trial.
Where it wins: price, simplicity, no hardware, native Sidecar quality. Where it loses: Apple-only, and it relies on private macOS interfaces, so a major macOS update may need a SideMini update before it works again. We say so on the box.
At a glance
| Sidecar | Luna Display | Duet Display | SideMini | |
|---|---|---|---|---|
| Cost | Free | ≈ $130 once | ≈ $25–40 / year | $9 once |
| Headless Mac mini | No | Yes (hardware) | No | Yes (virtual display) |
| Auto-connect at login | No | App must be running | App must be running | Yes |
| Reconnect after drop | Manual | Yes | Yes | Yes (≈ 2 s) |
| Windows / Android | No | PC as host | Yes | No |
| Apple Pencil, HiDPI | Yes | Yes | Partial | Yes (it is Sidecar) |
| Keeps the Mac awake / restarts after power cut | No | No | No | Yes (Server mode) |
| Extra hardware | No | Dongle | No | No |
Verdict
All-Apple desk, want it to just be there at every login: SideMini. Mac mini in a cupboard you will never sit at, or a PC in the mix: Luna Display. Need Windows and Android tablets: Duet. Just trying it out: Sidecar, for free, today.