Azure platform for hosting web applications, REST APIs, and mobile backends. Like renting a fully-furnished office space where you can immediately start working without setup.
A startup deploys their web application to Azure App Service and automatically gets scaling, security, and monitoring.
Azure App Service is a managed platform (PaaS) for hosting web apps and APIs with built-in deployment, scaling, TLS, and monitoring. AWS Elastic Beanstalk and Google App Engine provide similar PaaS-style app hosting and managed scaling. OCI does not have a single direct, like-for-like App Service product; teams typically use OCI Container Instances (for containerized web apps) or OCI Functions (for event-driven APIs) plus an API gateway/load balancer.