I just deployed a web app (node.js container and mongo container) using Azure multi-container instances. It's a bit like Docker Compose but works with an Azure specific yaml file: https://learn.microsoft.com/en-us/azure/container-instances/container-instances-multi-container-yaml
Now I see that there is something called "Azure Web App for Containers". This seems to work with a real docker compose yaml file.
Other than the configuration file format, are there any other differences?
Note: I'm talking about Azure container instances, not Azure container services.
Well, azure container instances bill you only for the time container is active, while webapp bill you for the time webapp exists (so all the time). that is one of the biggest differences between those.
But overall, I'd say Azure Web App for Containers is just a shortcut to run containers on existing "stuff". I've recently learned that Azure Web App for Containers offer kubernetes capabilities, so these 2 services evolve in a slightly different directions. Azure Web App for Containers is targeted at long running stuff (always running) while ACI are aimed at scheduled\burstable\short lived workloads (similar to Azure Functions).