Mr. Gestures for Xamarin v1.5.4
Xamarin Forms is great if you want to develop apps for different mobile platforms. But when it comes to touch gestures, it is still very limited.
For more than a year they only had the TapGestureRecognizer. Although they did add some others lately, they still don't provide all information which you need. Furthermore the API which they use has been copied from iOS and is not what a .NET developer would expect.