Retool is described as 'Your business needs software. But because engineers are scarce, many departments (sales, marketing, support, HR, etc.) don’t build the software they need. When companies use Retool, they build much more software, which leads to a more efficient business' and is an website in the development category. There are more than 50 alternatives to Retool, not only websites but also apps for a variety of platforms, including SaaS, Self-Hosted, Mac and Windows apps. The best Retool alternative is Teable. It's not free, so if you're looking for a free alternative, you could try Teable or Airtable. Other great sites and apps similar to Retool are Undb, Appsmith, Budibase and Tableau.
I like this product, and I believe they should have a promising future, hope we can see more features in following days.