Common scenarios for functions are as follows:

• Timer-based scenarios (for example, cron-jobs on databases for cleaning up)
• Event procession based on Webhooks (for example, export newly discovered data in a BLOB storage to a SQL database)
• SaaS event processing (for example, email in Outlook exports attachment to OneDrive)
• Serverless web application architectures (for example, transfer web page inputs to an automation script)
• Serverless mobile backends (for example, after a picture is taken, a thumbnail needs to be created)
• Real-time stream processing (for example, transform data of thousands of devices and save the important data to a database)

As you can see in this list, there is a wide variety of solution scenarios where Azure Functions really make sense.