How to properly organize Azure database and UWP+Xamarin?

Question

Microsoft Azure

Good afternoon colleagues. I'm looking into Azure + UWP and I'm confused. I'm making a UWP program (also looking towards Xamarin) that clients will have to download (purchase) and use a database in the cloud.
1. Did I understand correctly that clients must have an Azure account (I do not contact clients. They can be in different cities and countries)?
2. Should I use the Mobile App service for my development (And then the clients themselves must create this service with the database in their Azure account)?
PS base size ~100-500mb

Answer 1

1. no.
2. no.