A sales CRM — companies, contacts and a deal pipeline across lead / qualified / proposal / won / lost — over the app's own /api.
Open Salesline — CRM in the no-code builder and it reshapes itself as you chat — rename it, retheme it, add screens, change the data model. Publish when you are ready. You are not editing a page: the template is a complete product, with a web app, a native mobile app, a REST API and a seeded database.