Ninja Database Pro is deadly good. Ninja Database Pro is a lighting fast, compact, ACID compliant database. It can be used as a database for desktop applications, a Silverlight database, or a Windows Phone 7 database, an Android database with Xamarin's MonoDroid or an iPhone database with Xamarin's MonoTouch. It is the first database supporting either object database mode or relational database mode. You choose how to save your child objects as embedded or in a seperate table.