After trying a few cloud based ToDo applications with mobile apps etc. I gave up and started using org mode files from a text editor.
I think MS is trying to make tools like this for the C# world, but I haven't seen them yet.
Microsoft allows you to publish a web application from Visual Studio project to Azure.[1] It's very simple, but more much opinionated. It's a great trade-off for an individual developer who needs to focus on functionality. In the context of this discussion, there's an important distinction -- it's not an interface, it's just a feature. It's tightly coupled to Azure from one side and to Microsoft dev stack from the other.
[0] https://knative.dev/ [1] https://tutorials.visualstudio.com/aspnet-azure/publish
But many organizations would rather not directly pay the costs of app services and instead indirectly pay the costs by making their developers tool around with Kubernetes.
That actually wouldn't be bad, and probably faster than getting it running on Kubernetes.
So, a text editor?
[1] https://github.com/kubernetes-sigs?utf8=%E2%9C%93&q=cluster-...