Today I released a big new update for Side Mirror, my macOS app for presenters.

Before I dive into the new features, let me first try to explain what Side Mirror does.

This is truly the hardest part of developing this app. I have yet to find my good elevator pitch.

Side Mirror allows you to select any attached display on your Mac and run it in a window.

This can be useful for a number of reasons:

  • During live presentations, to avoid looking back at a projector screen. You can see it and monitor what the audience sees right on your Mac. This keeps your eyes front toward the audience. Your main screen can have presenter notes, snippets to copy & paste, files to drag, etc.

  • Using a cheap HDMI dummy adapter (like this one), you can get a virtual screen in macOS. Using Side Mirror, you can put this screen inside a window. There are 2 amazing reasons why this is powerful:

    • Presenting via Zoom. You can share your full “virtual” display and not have desktop icons or other windows visible to the audience.
    • Recording with Screenflow. Similar to above, but this time recording a full screen video without having to “prep” your desktop. Additionally this is a great way to have a dedicated, resolution-perfect display to record to simplify your workflow.

So that’s the core of Side Mirror.

In order to make using a display-in-a-window actually usable, there are a few key features

  • Teleporting your mouse clicks through the preview window and to where you actually clicked on the display (like magic 🪄)
  • Keyboard shortcut to bring your mouse back to the Side Mirror window, to help you avoid getting lost
  • Cursor preview hinting as your cursor moves to the external display, so you can easily tell if your mouse is on the display or on top of Side Mirror.

2.5 update features

So now that you (hopefully) understand what Side Mirror can do, here are the new features and fixes in 2.5.

New Resize option

Resize the Side Mirror window to match the target display resolution. You’re given 3 options to scale the Side Mirror window to match the target display. If it the main display can’t accommodate it, it does a best fit.

Snap Back Cursor

Enable this in preferences. This is a keyboard shortcut to have your mouse jump back to the Side Mirror window.

Cursor Hinting

Enable this in preferences. This will highlight the Side Mirror preview when your mouse moves to the target display. This can be useful as a guide to let you know which display your mouse is on. You can customize the color in preferences as well.

Remember last display

Side Mirror will now remember the last display used and automatically select it on subsequent launches, if it is available.

Keyboard Shortcuts

There’s now a keyboard shortcut to stop/start the preview

🐞Bug Fixes

  • Click-through is now disabled after you stop previewing
  • The preview will now be stopped if a display suddenly becomes unavailable
  • Displays that lack a title (or have an empty name) will now show “Untitled”
  • Fixed an issue that would cause the preview to suddenly stop

And one last thing, as I’m actually quite eager to start taking advantage of newer OS features, this will be the last release that supports macOS Catalina.

Available on the Mac App Store

You can find Side Mirror on the Mac App Store. I hope you enjoy it!