Many emerging web applications fail in spite of good developers and large marketing campaigns. But why is that and what makes successful web-app startups? I wrote down the most important foundations for new and successful web applications.

The most important foundations for successful web-apps:

1. The product must be useful and simple: Then users will love it and talk about it. Word-of-mouth is extremely valuable and effective. Even if it may not replace traditional web marketing completely. You have to love and use your own product, otherwise you will fail.
2. Early business model to generate income: The business model should be defined clearly from the beginning. If the product is really good, users are willing to pay for it. It is much harder to monetize the product afterwards.
3. User feedback and testing: Design and development are processes, and who dares wins. Release more, pay attention to user feedback, test a lot (A/B and UX-Tests) and continuously improve the product on that basis. However, it is important to ensure that you do not add unnecessary features, that complicate your web-app too much.
4. Be patient: The famous overnight success is extremely rare. Slow but steady growth for your web-app is better than a huge hype, which flattens out after a short time. Such hype would also show that your web-app has no benefit for the user in the long run.

If you have more basic tips, I will gladly include them.