30-second version: I built Lasso for people who teach on a shared Mac screen and need to point at something without leaving the window. Press Option-Shift-A, draw over your code or slides, press Escape when you're done. Students see the marks if you share the entire display. It's $4.99 once, no subscription. I'm the person who makes it.

If you teach people to code over a video call, you already know the failure mode. You're in VS Code or a terminal, you say "this line, right here," and the student is still hunting for your cursor. On a 13-inch window, at 30 frames per second, a tiny pointer is a weak teaching tool.

This isn't a new complaint. In r/macapps, someone planning a live tutorial asked for a way to draw, circle, and put text on a shared screen, because visual cues were going to matter more than a polished deck. Another person who runs weekly online lessons wrote that they were stuck with a meeting app's built-in tools, and those tools were not good enough. I didn't invent a classroom full of testimonials. I just kept seeing the same request, and I already had a Mac app that does this job.

Lasso is a drawing overlay. It sits on top of whatever you're already teaching from: an editor, a browser, a slide, a worksheet. You don't switch into a separate whiteboard unless you want to.

A lesson, from setup to "any questions?"

Install Lasso, drag it to Applications, and leave it in the menu bar. The default shortcut is Option-Shift-A. You can change that in Settings → Shortcuts.

Before the call, open the repo or the slides you'll actually use. Close anything you don't want on a shared display. In Zoom, Google Meet, or Microsoft Teams, share the entire display you will draw on, not a single VS Code window and not a Chrome tab. Lasso's marks sit in a layer over the screen. A window-only or tab-only share can leave them out. Check the share preview, or ask the first student whether they can see a test circle, before you start explaining for real.

When you need to point, press Option-Shift-A. While you're drawing, the keys are simple:

  • P for the pen
  • H for a highlighter that doesn't cover the code
  • A for an arrow
  • C for numbered steps (click once per step)
  • F for a fading laser pointer
  • E for the eraser, and Command-Z to undo
  • Escape to clear the marks and go back to typing

I use numbered steps more than anything else when I walk through a function. Click 1 on the input, 2 on the messy conditional, 3 on the return. The student can follow the order without me saying "no, the other if."

If a question needs a diagram, press W for a whiteboard (or K for a blackboard), sketch it, then go back to the editor. You can pin a drawing if you want the marks to stay up while you click through the apps underneath.

Recording a lesson, or sending a still

The marks are on the screen itself, so they show up in a screen recording if that recording is capturing the display you're drawing on. That's the path I have in mind for a short homework recap, or a clip you send after class. Lasso is not itself a meeting recorder. Use whatever you already use to record, and share or capture the whole display.

You can also press S for a full-screen shot, or Shift-S for an area, and drop the annotated image into Slack, email, or the course chat. Capturing a screenshot (and using blur) needs macOS Screen Recording permission. Drawing alone does not. If a student later asks "which line?", you have the picture.

Blur, if you need it, is the B key. It's a still patch. It does not follow code as you scroll, so don't treat it like perfect redaction.

You don't need a tablet for this

A lot of tutors end up buying a drawing tablet, or pairing an iPad, just so they can write on a problem. That works, and for handwriting-heavy math it may still be better. It is also, as one tutor put it when schools first went remote, annoying to set up and keep working alongside a laptop camera and a call. For circling a line of code or numbering three steps, a $4.99 overlay on the Mac you already teach from is a simpler tool.

Lasso is a one-time payment, including tax as shown at checkout, with no account and no subscription. It runs on macOS 14 Sonoma or later, Apple silicon or Intel. It's signed and notarized.

A light note on AI, because some of you will ask

Lasso also ships a local MCP server. Claude Code, Cursor, or Claude Desktop can connect on the same Mac, see what you circled, and draw an arrow back. The tools do not click or type into other apps. I mention this only because some coding tutors already live in those clients. It is optional. The teaching workflow above does not depend on it. Setup lives in Settings → Agents, and the MCP guide has the one-liners if you want them.

If you do connect an agent, remember that your AI client may send screenshots it receives to its model provider. And don't put a student's homework into a model unless that's appropriate.

What it doesn't do

It's Mac only.

Students do not get their own pen. This is a presenter-side overlay. They can see your marks in the shared display. If you need a shared whiteboard everyone can draw on, use the meeting app's tools for that part.

If people on the call can't see what you're drawing, it's almost always the share source. Stop, share the entire display, and check again.

Live capture and blur need Screen Recording permission. If you only draw, you can skip that until you want a screenshot.

If you want to try it on a real lesson

Lasso is at https://www.trylasso.online/. Four dollars and ninety-nine cents, once.

Do a two-minute test share before the first class: draw a circle, ask if it's visible, press Escape. If something about the overlay or the shortcut feels off in Zoom or Meet, tell me which app you were teaching in.