I agree with what @codegeek has said, and would like to outline a few more pointers: - It's important to solve a problem you've either deeply experienced or pa

I agree with what @codegeek has said, and would like to outline a few more pointers: - It's important to solve a problem you've either deeply experienced or passionate about. Having a deep passion will help you build something that others will more-than-likely use. This passion also lends itself well when it comes to selling (people tend to buy _you_ just as much as the product). - If you don't know what to build, go to your favorite open-source project and do some sorting (comments or reactions). This is likely an indicator of a larger issue, which means people are looking for a solution. - Definitely listen to your customers. Sometimes it's a simple bug that needs fixing, other times it's a feature that will not only make them happy, but help make your business more attractive to future clients that might be facing similar. FWIW I'm running a successful (by my terms) side-project called https://browserless.io https://browserless.io. I've also done an interview on IndieHackers and you can see more about it here (https://www.indiehackers.com/product/browserless https://www.indiehackers.com/product/browserless)