How a simple Chrome extension with no ads grew to 400K+ users and started making money
Hi, my name is Igor Zuev. I have a background in diplomacy and spent several years working in Europe. At some point, I realized I didn’t want to build a traditional career — I wanted to create my own IT products for a global market.
At first, I was doing client work. But pretty quickly it became clear: services are hard to scale. So I shifted my focus to building my own products.
Since then, I’ve launched dozens of micro-products, reached millions of users, and grown to over $1.5M in annual revenue.
In this case study, I’ll break down one of my projects: Dark Mode for Google Docs.
This is not a story about venture funding, big teams, or years of development.
It’s the opposite — a very simple product, built quickly, launched without paid traffic, and grown on top of existing demand.
About Dark Mode for Google Docs
At first glance, the idea looks too simple to make money. But in reality, these kinds of products often perform the best.
Instead of trying to invent something new, you take a clear problem people already want to solve — and build a simple, convenient tool for it.
In this case study, I’ll show:
- how the idea came up
- how the first version was built
- what drove the growth
- and how the product started making money
Where the idea came from
This is not a one-time success or luck.
I don’t come up with ideas like “let’s build a startup.” My approach is different — I start from demand.
I build products around existing traffic. No complex architecture, no months of development, and no guessing.
The logic is simple: first find what people are already searching for → then build a solution for it.
Not “better than everyone else,” but simpler and clearer for a specific use case.
Most people do the opposite: they start with an idea and then try to find demand. That’s why most products fail.
In this case, everything was obvious:
- demand already existed
- solutions already existed
- users were already searching
The goal was not to invent something new, but to fit into existing demand.
Make it simpler
I didn’t try to make the product “better.” I made it simpler.
I took one specific task — enabling dark mode in Google Docs — and removed everything unnecessary.
The result is a very simple flow: open → enable → use.
No extra settings, no complex UI, no learning curve.
This directly impacts key metrics:
- higher install conversion
- better retention
- better user experience
How I built the first version
I didn’t build the product from scratch.
I took an open-source solution and repackaged it for a specific use case: simplified the logic, removed unnecessary parts, and adapted it for Google Docs.
It wasn’t traditional development — it was fast assembly.
The first version took about a week. No team, no complex architecture, no perfectionism.
Just a version good enough to:
- get first users
- test market reaction
- move forward
Growth
The start was slow — around 100–200 installs in the first couple of months.
No spikes. No “viral growth.”
But then the product started growing steadily — and that wasn’t random.
It was built on existing demand, so:
- no need to explain value
- no need to warm up users
- no need to “sell”
People were already searching for a solution. They just needed a simple tool.
Main traffic sources:
- search engines
- Chrome Web Store
Important note: all growth is organic. A big part of this is SEO and optimization for the Chrome Web Store. In my products, I focus heavily on distribution — it’s 80% of the work. But that’s a separate topic.
Monetization
I didn’t monetize immediately.
First, the product delivered value. That’s critical.
The user needs to:
- install the product
- start using it
- integrate it into daily workflow
Only after that — introduce a paywall.
At that point, value is obvious. No need to explain why to pay.
Conversion happens naturally — without pressure or aggressive selling.
Why people pay for such a simple feature
It may seem strange to pay for something so simple.
But it’s not about complexity. It’s about:
- how often the product is used
- how deeply it’s integrated into workflow
If someone uses Google Docs every day, dark mode becomes part of their environment.
And if a tool consistently improves your experience — you’re willing to pay for it.
Revenue
Right now, the extension generates around $600–700/month.
Monetization didn’t come immediately. For a long time, the product made $0 — that was intentional.
First audience → then monetization.
Also, many users joined before the paywall and still use it for free.
The model is simple:
- subscription → recurring revenue
- lifetime → one-time payments
Interesting detail: more than 50% of paying users choose the lifetime plan — the most expensive option.
What this case really shows
- Don’t invent — find demand
- Don’t build complex — solve one problem
- Don’t add — remove
- Don’t delay — launch fast
This is what actually drives results.
And the key idea:
If solutions already exist — it’s not a problem.
It means there is already demand and money in the niche.
The only question is: can you make it simpler and clearer for a specific use case?