SQL Azure Data Sync does not currently support the mobile scenarios. The current preview and the GA version focuses on link on-premises SQL Server with SQL Azure, as well as syncing multiple SQL Azure databases. To work with SQL Server we require the download of a small Windows service which only works with SQL Server.
Having said that, mobile scenarios are definitely still of interest to us. Can you email me and I'll follow-up with you directly to get more information about your scenarios - mark.scurrell at microsoft dot com