Setup: MacMini + iPad Pro

With the release of the new Magic Keyboard for the iPad Pro, Apple once again positions the iPad Pro as a viable primary computer and alternative to a laptop or desktop. The Magic Keyboard includes a built-in trackpad to take advantage of full trackpad support that iPadOS 13.3 now offers.

The iPad, since the first model and more recently with the Pro models, has variously been my primary computer, my travel computer, or a computer to supplement a Windows laptop. The hope and ambition have always been for it to fulfill that central role.

However, while iPadOS 13 brought new multitasking features and an upgrade to Safari, it also changed the way it managed background apps, which led to backgrounded apps to refresh more often and thus constrained the ability to switch between apps. This is a limitation compared with laptops and desktops. I can live with this while on the road, but not when at a desk.

I explored the option to supplement the iPad Pro (Gen 3, 12.9") with a MacMini as a desktop setup with the iPad as the primary display for the MacMini.

Duet Display is well known, but as the name implies, it is designed with the intention for the iPad to be a secondary device. The MacMini has a limitation that requires it to detect a primary display before it will output to a secondary display. Duet Display requires its app to be running on both the MacMini and the iPad. There is a hack that involves a “ghost” display, an HDMI dongle that simulates a primary display.

A more elegant and stable solution, which also requires a dongle, is Luna Display. By the makers of Astropad, a popular app that enables one to use an iPad and Pencil as a graphic tablet input for the Mac, the Luna Display team had a similar idea, which is documented here.

There is the native option of Apple Sidecar which, similar to Duet, requires the dongle hack.

I’ve found Luna Display to be the most stable method and this mode of computing has addressed the use-cases I’d hoped it would and opened up a few new, unexpected ones.

With this setup one gets a touch screen Mac with a USB-C powered monitor that has a tiny footprint. Given that this monitor is an iPad, it also works with the Apple Pencil.

This is a boon to apps that benefit from fine input, such as Adobe Lightroom and Photoshop. Both have capable iPadOS apps, but there remain features that as desktop only. Other features are constrained on the iPad, such as the heal tool in Lightroom. The iPad struggles when multiple or large spots have been healed. This isn’t the case with the MacMini. The heal tool on desktop is also more intelligent and powerful.

This is an example of the primary use-case, the ability to switch between macOS and iPadOS, and the setup has delivered on this. To move between the two OSes, one minimizes the Luna Display app to use iOS and re-opens it to use macOS.

Slide Over is available to quickly dip into an iOS but sadly Split View isn’t — snapping iOS and macOS apps side-by-side would be very cool, but I expect there’s a technical limitation that prevents this, given that it’s a feature other users have requested.

My biggest niggle is the inability to pair the Magic Keyboard and Magic Trackpad to both the MacMini and the iPad Pro at the same time (and toggle between them). There is a bit of cognitive dissonance when one switches from hardware to touch input and back again.

Spotify behaves in an interesting way, given that you can use the Spotify app on any one device as a remote to control what’s playing on another device. After trying a few configurations I’ve landed on mostly having my Airpods connected to the iPad and playing Spotify from there and controlling it by touch on the Airpods, or Spotify iOS via Slide Over. If I need to listen to something on the MacMini I toggle the Airpods to the MacMini and then back to the iPad for music. It’s a bit clunky but this enables me to pick up the iPad and use it standalone more easily.

The feature that I’ve used the least is Luna’s wireless display. It performs better than I expected it to (i.e. with less lag). But I found it rare that I need to use the MacMini when I’m not seated right in front of it and browser tabs sync across devices anyway.

The minimal footprint, flexibility, extensibility, and portability of this setup have made it a pleasure to work with.