App crashed with unclear reason in Xamarin.Forms 1.1.0.6201

Hi guys,

I'm developing an application using Xamarin.Forms 1.1.0.6201 and I'm getting problem with unhandled exception from it.
You can see the error here:

System.NullReferenceException: Object reference not set to an instance of an object ==> at Xamarin.Forms.NavigationProxy.set_Inner (INavigation value) [0x00000] in <filename unknown>:0 ==> at Xamarin.Forms.Platform.Android.Platform.SetPage (Xamarin.Forms.Page newRoot) [0x00000] in <filename unknown>:0 ==> at Xamarin.Forms.Platform.Android.AndroidActivity.SetPage (Xamarin.Forms.Page page) [0x00000] in <filename unknown>:0 ==> at SmartCarPhone.Droid.MainActivity.OnCreate

I'm not sure whether this problem is from the current XF version or from somewhere else.
Did any of you meet this problem before?

Sorry for my English