Thank you for contacting us! Yes, you can share the viewmodel between WPF and Xamarin Forms apps.
Our Xamarin Forms components share their code through portable libraries including the attributes used by DataForm.
In order to us the attributes you would need to add reference the the following assemblies and its xamarin dependencies if needed:
Please, find the iamgeof the portable profile that these assemblies support -http://screencast.com/t/JhJZlQOWLj
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