I tend to think that the job of invoking the services lies within a gateway. For example, you can have a microservice for recipes, but a web gateway that know all of the various integrations necessary to generate a page. So the web gateway is essentially a monolith.

If and when you need to support mobile devices independently of your web UI, you can have a mobile gateway. Same idea. This gateway is optimized to know how to handle mobile traffic realities like smaller download sizes, etc.