Developing an Azure Sql Database backup strategy
There are a number of ways to schedule jobs for Azure SQL DB such as elastic jobs or azure automation. They can be setup to export your database at the intervals you require so it provide similar coverage as backups. Not the same experience and will be pretty klunky if your databases grow to massive sizes but in the few to tens of GB, you won't miss the super powers of local SQL Server backup (e.g. compression).

The team is trying to provide a solution for the long term retention requirement for backups so if it's important to you, add the request to https://feedback.azure.com/forums/217321-sql-database. I don't know what state that investigation is in but always helpful to get users chiming in with requirements so be very explicit on how long you really need to keep the backups around.