- Music Tuners
- Rulers/ measurement tools
- Tools using gyroscope (record speed indicator)
Take a simple idea and continue developing it until the user experience is really enjoyable. Not guaranteed to succeed, but a compelling way to spend your time.
You have to find ways of getting your message out. No matter how good your product is, if your users can't find it, you won't sell anything.
This is probably why it's important to make sure you're not doing it for the "easy money" and also why it can take months or years to make a nice little passive income; the word takes a while to get out.
I have to question these "I spent years making $40 a month working 8 hours after hours to built <project> but now <project> makes $60k a month" stories, since at some point you really have to ask yourself how much your time is worth. Thousands of hours for $1M pre-tax, not to mention how much life you gave up for that is kind of idiotic IMO.
My metric generally is, "if someone on etsy selling magic rocks is making more than my tech project after three months, time to move on". I'm not being shitty, this is just a standard I hold myself to when it comes to valuing my personal time. Also, don't worry, I'm not one of these people who thinks my time isn't worth cooking or cleaning (like many YT gurus and even Financial Samurai now claim).
Some people have said that this was far more effective than advertising. And it’s free.
But most importantly, you need a following, an audience to sell your product to.