I wrote a guest article for an IT consultancy on Azure SQL Database, more specifically DTUs and vCore options. At a high level I discuss what both options are, the differences and what you should select. Hopefully you will find it useful. Please see the link below:
vCore based performance levels are very new, currently in preview and not yet rolled out to all Azure regions (The preview is not available in the following regions: West Europe, France Central, UK South, and UK West.). It does offer a totally different approach to sizing your database.
If you know me by now I like rebuilding indexes and that is no different in Azure. Now we have the ability to resume a paused rebuilding operation rather than cancelling it (Feature currently in public preview). I like this because I have the flexibility to pause it if I feel that it is taking up too much DTU (Database Transaction Unit) usage hence I can free up resources for other operations.