How to Stream One Mac Window to Your iPhone

Updated October 2026 · 3 min read

A whole Mac screen on a phone is a lot of small things. Often you only care about one of them: a video, a build log, a chat, a progress bar. Streaming just that window makes it fill your phone, and the rest of your desktop stays on the Mac.

Before you start

You need Beam on your iPhone or iPad and Beacon on your Mac, already paired. If you haven't set them up yet, the setup guide takes a couple of minutes. Picking a window from the phone works with current versions of both apps. Beacon updates itself.

Pick a window from your phone

1. Start a stream in Beam as usual.
2. Tap the stream once to show the controls, then tap the window button in the top bar (it looks like a small Mac window).
3. The Capture sheet lists the windows open on your Mac, by title and app. Pull down to refresh it if you just opened something.
4. Tap a window. The sheet closes and the stream switches to it.

To go back to everything, open the same sheet and tap Full Display. The current choice has a checkmark next to it.

What you'll see

• Just the window, without the menu bar, the Dock or anything around it.
• The window's own shape. A tall chat window fills a phone held upright. A wide video fills it held sideways. Picture in Picture follows the same shape, so a tall window gets a tall floating player with no black bars.
• It keeps streaming when covered. You can keep working on the Mac in other windows, and the phone still shows the one you picked.
• Sound is still the whole Mac's. Beam streams system audio, so you'll hear every app, not only the one in the window. Turn audio off with the speaker button if you don't want it.

Click mode works on a window too. A tap lands on the same spot in that window on the Mac, even when it's zoomed or cropped on your phone.

From the Mac side

Pick a window in Beacon

Click the Beacon icon in the menu bar and choose Beam a Specific Window…. You get live previews of your windows to pick from, which is handy when several windows have similar titles.

Switch with a keyboard shortcut

In Beacon's Settings, the General tab has a Global Hotkey section. Turn on "Toggle window mode from anywhere" and record a shortcut to switch window mode on and off without opening any menus.

Always start on the same window

If you always watch the same thing, say a terminal or a dashboard, set it as the default. In Beacon's Settings, open the Display tab and choose a Default Target under On Connect. When a stream starts, Beacon looks for that window by app and title. If it's closed, Beacon uses another window from the same app, and if the app has no windows open, the full display. Leave it on "No default" and each stream starts on whatever you streamed last.

Streaming a video in Picture in Picture

Pop a video out into Picture in Picture on the Mac, in Safari, Chrome or QuickTime, and the floating video window shows up in Beam's window list. Pick it and your phone gets only the video, with nothing else around it. Turn on Picture in Picture on the phone too, and the video floats over whatever else you're doing there.

If something's off

• The window isn't in the list. The list only shows windows open on the Mac's current desktop. Un-minimize the window, bring it onto the current Space or out of full screen, then pull down to refresh. Very small windows, under 100 pixels on a side, are left out.
• The list says there are no windows. Open something on the Mac and pull to refresh. If it stays empty, check that Beacon still has Screen Recording permission in System Settings, Privacy & Security.
• The window closed. Open the Capture sheet and pick another window or Full Display.
• Text looks soft. A window is often much smaller than the full display, so the stream has plenty of room for detail. If it still looks soft, raise the quality preset or set the stream mode to Video. The quality guide explains both.

A window, or a cropped area?

Beam also has a viewport lock: tap the lock button, drag out a rectangle on the stream, and Beam crops to it. While you're choosing, touch and hold on a playing video and Beam finds its edges for you. Use the viewport lock for part of a window, such as the player inside a web page. Use window mode when you want the whole window, and want it to keep streaming when you cover it on the Mac.

Frequently asked questions