If you like this idea checkout suckless software (https://suckless.org/). I've finally had the free time lately to start tweaking their "recipes".

Yes, this is an excellent example.

I was also thinking of all those little online tools that solve trivial problems like formatting JSON, decoding URL parameters etc.

Any unprofitable problem can be redefined from "How to Solve Unprofitable Problem X for Me or Friends, Etc." to "How to Solve Problem X Profitably".

Even small problems may be hidden economic launch pads, given that the ingenuity to make their solutions profitable is likely to provide surprising insights.

Generic approaches to making an unprofitable niche more profitable to serve:

- Generalize the problem in some novel but useful way, so the solution has increased market size

- Generalize to a user customizable solution, to offload costs of complete specialization

- Reduce the costs of creating the solution in some way, such as new specialized tooling

- Divide up the problem/solution into subproblems/solutions whose potential value as a flexible toolkit is greater than a monolithic solution.

- Identify a small market that having adopted a small unprofitable solution will now be easy customers for related products, i.e. amortizing the initial cost across the long term value of customer contacts

Thinking deeply about the specifics of a problem once may result in more novel specific approaches.

Some problems just aren't that valuable to solve. I use tons of neat little tools like jsondiff.com that just aren't really worth paying for. Monetising those products would make them less pleasant to use, and I'd move to something else.

Some things can just remain simple and free, and that's fine.

While we are at it, I created an app for my 3rd grader. Just her. It has 1 user.

What does it do?

Math practice http://arcadejack.com

This is exactly what my son needs right now.

Thank you so much!

2x the userbase overnight? Is this growth hacking?

Found that hockey stick growth. Time to call up some VCs.

Just tried it. Nice. Couple of "issues" a) Answers are carrying over from one question to the next and not getting cleared automatically b) When I answer a question, the animation disables the controls and I have to click again to enable and move to next question.

Tested on 74.0 (64-bit) on OSX. These might not be "issues" and how you defined the experience for your little one. If so, feel free to ignore.

Thanks for checking it out. a) seems like a bug, but I can't recreate. After I click "next" for the next problem, the answer field is empty. Let me test some more b) yes, this is indeed a weird UX and my daughter said it is "annoying". But it exists so that the kid gets a pause to know whether the answer was right or wrong. I should maybe show it for 3 seconds and proceed to next automatically.

Will upload new version of the site tomorrow now that I have a full two users for the app :)