On Turning An Online Solitaire Game Into A $1.5K/Month Side Hustle

Published: July 21st, 2020
Holger Sindbaek
Founder, Online Solitaire
Online Solitaire
from Copenhagen, Capital Region of Denmark, Denmark
started June 2018
market size
avg revenue (monthly)
starting costs
gross margin
time to build
210 days
growth channels
Word of mouth
business model
best tools
Moz, Google Drive, Twitter
time investment
Side project
pros & cons
35 Pros & Cons
9 Tips
Discover what tools Holger recommends to grow your business!
Discover what books Holger recommends to grow your business!

Hello! Who are you and what business did you start?

Hello everybody! My name is Holger and I’m a designer-turned-developer from Denmark. In the last couple of years, I’ve been working on a solitaire gaming website called Online Solitaire, which features the most popular solitaire games such as Klondike, Spider, and Freecell.

The game itself has actually been somewhat of a side-hustle of mine for a while now. It initially started years back as a Mac app that was sold through the Mac App Store, where it earned around $800 a month.

After having made the app, I ended up going to New York to start a startup called Slang which was a marketplace for sneakers and streetwear, with a friend of mine. That venture effectively led me to have my solitaire app on a perpetual backburner. And after a few years of no maintenance, the app got so buggy it was eventually thrown off the app store.

Sadly, I and my friend’s startup got beaten by our competitors after a few years as well and after 3 years of hard work, I felt somewhat burned out and I frankly didn’t know what to do next. I ended up taking some time off to figure things out and maybe work on a project on a much smaller scale. That led me to build solitaire once again, but now for the web.

At the moment Online Solitaire earns about $1,500 each month and I hope/expect that number to go up in the future.


What's your backstory and how did you come up with the idea?

I’m a designer-turned-developer and I’d like to say that means I can assume either role as competently as any designer or developer out there, but realistically it means that I’m not brilliant at either. Where I do shine is in the cross-section of those two disciplines.

With most solitaire websites you’ll find out there, you get the sense that they’ve been made by a programmer who hasn’t put much energy into the design. So having that design background gives you an edge on these small scale projects, that are too small to get a team to do it.

But let’s talk about why I chose to do a solitaire app. I’d be lying if I claimed it was because of a burning passion for playing solitaire (though I don’t judge if you have one - many people do). The truth is that I had an aching to try my hands on a new programming language and to see if I could create some passive income.

I had read Robert McKenzies’ yearly reports for some years by then and I was quite fascinated by how he managed to earn a (relatively) passive income on his website Bingo Card Creator. The site itself didn’t seem like the most difficult thing to create or the most interesting for that matter. So it seemed to me that it was all about choosing the right product.

I ended up doing something similar. Similar in the sense that I didn’t want to “invent” something new, I simply wanted to find an app people were already using and create a better version. I ended up having the following criteria for the app I was going to work on:

  • The main source of new users had to come from search since I hated doing marketing.

  • I wanted the app to already exist, so I knew that people wanted it and I wanted the app to be of such quality that I knew I could make something better.

  • I wanted the improvement of the app to be partially about the design since I saw that as one of my strengths.

  • I wanted to be able to create the initial version of the app within a few weeks, so it wasn’t too much of a catastrophe if people didn’t use it.

I already had some experience with the Mac App Store (MAS), having built a topbar calculator a few years prior and I knew that many of the apps in the MAS were of questionable quality, so I thought that looking into the MAS would be a good start.

If I were to start over, I'd focus a lot more on the things I really don’t like doing.

I ended up writing a script that scraped App Annie, which lists all apps in the MAS, for games, and ended up with a list of games that I ranked based on estimated revenue, average rating, whether the app was actively updated and so forth.


On the basis of that, I ended up going with solitaire, since there were multiple solitaire versions, like Spider and Freecell, on the list and I thought I could do a better version.

Take us through the process of designing, prototyping, and manufacturing your first product.

The initial design for the MAS version of the app was more lifelike, in the sense that the cards weren’t all aligned like they wouldn’t be if you were playing with a real deck of cards.


Big surprise, people just thought there was something wrong with the game, so I turned it into an optional feature and shortly after removed it completely. I guess I learned a lesson on going too far with skeuomorphism.

Both the MAS and the web version of the app were done in less than a month of full-time work and then released. This is really important in relation to user feedback. I know you’ve heard it again and again, but the mentality of creating an MVC (minimal viable product) and releasing as fast as possible holds true when it comes to part-time projects as well.

After the initial release of the app, most of my decisions were guided by my users. Users will let you know when they’re happy and especially when they’re unhappy. You just have to take all that feedback with a smile and take it into consideration when it comes to creating new features.

Describe the process of launching the business.

There really was no launch. Everyone knows what solitaire is and no-one is going to write about your new innovative solitaire game. Everyone knows what it is and not much new can be said about it.

The thought of playing solitaire enters people's mind and then they search for it. In other words, it’s all about SEO.

Since launch, what has worked to attract and retain customers?

As mentioned, users find solitaire games by searching for them, so it’s all about having your site pop up whenever users search for solitaire-related search terms. I’ve been optimizing my pages using Moz’s on-page optimization tool and I’ve been working a little on doing some backlinking. The site is not ranking super well, but it’s getting around 1000 clicks a day from Google.

At one point it was getting around 2000 clicks a day, but due to a foul-up on my part, it’s back down again. The site used to be hosted on another domain, but when I got the chance to buy online-solitaire.com, I jumped on it. It seemed like a much better domain than the one I had. The foul-up consisted of me forgetting to pay the bill for the old domain, which was still redirecting old backlinks to the new site and therefore helping with SEO.


How are you doing today and what does the future look like?

Today the site is earning around $1,500 a month. Of course, I’d like it to earn more, but first of all, I’d like to keep the site a side-hustle. I don’t want to be dependent on the site. Believe it or not, there’s actually a good deal of competition out there, so trying to make the site a main source of income would probably give me sleepless nights.

During this summer I want to implement some more varieties of solitaire as well. Right now I’ve implemented the three most popular variations, Klondike, Spider, and Freecell, but there is an abundance of variations out there just waiting to be implemented. I’m not sure where to start and where to end. We’ll see.

Through starting the business, have you learned anything particularly helpful or advantageous?

If I were to start over, I'd focus a lot more on the things I really don’t like doing. As a one-person team, there’s really no-one else to “those other things”, whatever they may be. Since it’s never too late to start, that’s one of the things I want to become better at going forward.

For me, that’s marketing and SEO. I’ve been doing some on-page optimization and some link-building on a smaller scale, but there’s really no way around if I want to start ranking better on Google, I’ll have to become better at anything and everything related to SEO.

What platform/tools do you use for your business?

The app itself is based on React, with Firebase being used to handle users and database-related things. I really like how easy Firebase makes life in relation to user and database management. If you haven’t tried it yet I can highly recommend it. I’ve used Firebase both to React and React Native and loved it both times.

I’ve made a downloadable version of the solitaire game using ToDesktop. It’s basically a service that lets you make a website and make an app version of it for Mac, Windows, and Linux. They’re still relatively new, but I can highly recommend them.

I’m using GSAP for animations, and yes, you do need an animation library for a game like this. It might not seem like the most animation-intensive game, but there are enough animations that it’ll make your brain hurt if you don’t use a library like GSAP.

What have been the most influential books, podcasts, or other resources?

Most of the things I’ve read in this genre have been startup-related. There are a lot of good books out there such as Peter Thiel’s Zero To One, Rework by the founders of Basecamp, and many others that I’m sure to have been mentioned many times before on this site. You can use certain concepts and advice from those kinds of books, but a lot of it doesn’t necessarily apply to a side-hustle such as Online Solitaire.

The last year or two I’ve been looking much more into sites like Starter Story and Indie Hackers. They definitely have their startup-type stories, but they also have a lot of people who are trying to get a smaller project off ground or simply have a side-project going that they’re earning some revenue on.

Advice for other entrepreneurs who want to get started or are just starting out?

If you’re looking to start a new venture, then really consider which size you want that venture to be. Are you looking to create a side-project that earns a bit of revenue? A smaller business that can sustain you? Or do you want to create a startup with all that entails, such as venture capital and long hours each day for years on end?

All of those things are fine, but they’re wildly different roads to take and demand different levels of dedication and skill from you.

Whichever kind of venture seems to be the right for you, you need to know your strengths and weaknesses.

As for your strengths, it’s good to know what gives you an edge over other people. What exactly makes you the right person to do that specific project? Scott Adams, the creator of Dilbert, wrote in his book How to Fail at Almost Everything and Still Win Big, that what made him one of the only persons who could create Dilbert was a combination of him having been in the corporate world long enough to see the absurdity in it, having writing skills decent enough to write the comics, drawing skills (barely) decent enough to draw the comics and being so tired of what he was doing that he was willing to spend time and energy trying to get the comic published. So what makes you the right person for doing the project you want to embark on?

As for your weaknesses, we can’t be good at everything. If you’re doing a project with another person, that person should probably compliment your skills. If you’re doing a project alone, you better become decent at all the skills that project needs to succeed or find a person who can help you with the things you’re not good at.

I spent the better part of last summer working on a habit tracker for iOS called Habitual, which never really took off, partly due to my non-existing marketing skills. I could have spent that time on the beach instead if I listened to my own advice :-). I’m still using and maintaining that app, so if you’re a marketeer of sorts and see potential in it, let me know.

Where can we go to learn more?

Feel free to ask any questions and I’ll do my best to answer below.

Want to create a card game? Learn more ➜