I Built a Chrome Extension in 5 Months as a Teenager: Here’s My CometNotes Story

A teen from India — Mon, 04 May 2026 14:03:31 +0000

“I’m 11, I don’t have a CS degree, Here’s how I built an extension with AI”

The Problem

I had a problem.

Every time I had an idea, I’d think: “I should write that down.”

By the time I opened Notion, my mind had already moved on.

I’d lose the idea.

This happened constantly. I’d be in a meeting, get an insight, and realize 5 minutes

later I never captured it.

So I started testing different apps:

Notion: Too slow (5–10 seconds to open)
OneNote: Syncing issues
Apple Notes: Works okay, but can’t use on my work laptop
Google Keep: Too simple, no organization
None of them felt fast.

Why Speed Matters (And Why You Don’t Know It Yet)

There’s a psychological principle called “working memory.”

Your brain can hold about 5–7 ideas at once, for about 20 seconds.

If you don’t capture an idea within those 20 seconds, it’s gone. Forever.

Most note apps add friction:

Open the app (2–5 seconds)
Click “new note” (1 second)
Type title (5 seconds)
Start typing (2 seconds)

Total: 10–13 seconds. You’ve already lost half your working memory.

And that’s if the app is already open.

The “Aha” Moment

One day I was using Slack, and I realized something:

Slack uses keyboard shortcuts. Cmd+K to search. Cmd+/ for help.

Shortcuts are fast. Instant. No UI, no navigation.

I thought: What if my note extension could work the same speed?

One button Type your thought. Done.

No app to open. 0.2 seconds.

So I built it.

— -

What I Built

CometNotes is simple:

Press a single icon (or Ctrl+K on Windows)
Type or highlight your note (appears instantly)

Become a Medium member

Hit + (note saved)
Done

That’s the core.

Everything else is secondary:

Organize by categories and tags
Search (single search bar)
Sync across devices (just one key)

The Results

I launched a CometNotes PRO to 25 friends.

The feedback was unanimous: “Great.”

Not “This is so pretty” or “This has amazing features.”

Just: “It’s fast.”

I realized: People don’t want more features. They want to save time.

So I focused on making it even faster:

Removed animations (saved 0.1s)
Pre-loaded the note UI (saved 0.1s)
Removed account requirement (saved 0.5s)

Total: 0.2 seconds from highlighting to capturing.

The Launch

I built for 5 months, testing with 25 early users (friends, family, online communities). The feedback was unanimous: “This is so fast.” Not “This is beautiful” or “This has amazing features.” Just: ”It’s fast.” That’s when I knew I was solving the right problem.

Lessons I Learned

Lesson 1: Speed is a Feature

Your UI, design, and features matter way less than speed. Make your core

action 10x faster than competitors.

Lesson 2: Solve One Problem

I could have built a full Notion replacement. But I didn’t. I solved:

“How do I capture an idea instantly?”

That focus is what makes it good.

Lesson 3: Friction Kills Adoption

Every signup, every email verification, every “welcome” screen kills 50% of

your users.

CometNotes has zero of those.

Why I’m Sharing this?

I’m 11. I don’t have a computer science degree. I didn’t go to a coding bootcamp. I had an idea and 5 months of persistence. I built CometNotes PRO to prove something: You don’t need to be a professional developer to build something that helps people. If you’re scared to start because you “don’t know how to code,” this is for you. I used AI to help with 90% of the code. But I learned the concepts, debugged the problems, and shipped a real product that people are using. You can too.

The Future

Available on all major browsers — no account, no email, no tracking: — Add to Chrome — Add to Edge — Add to FireFox Try it now. Highlight and start making and organizing. If it saves you time, that’s all I ask. And if you like it, leaving a review on your store helps other people find it.

What’s Your Biggest Friction Point?

What app do you lose ideas to? What takes you too long?

Drop a comment. I read everything and ship features based on feedback.

P.S. — “If you’re building something, don’t wait until it’s perfect to share. Share when it works. Feedback will make it better.”

DEV Community: A teen from India