For too long I scratched my head over this, and I did not find any information that helps online. I tried to change the target / minimum frameworks, and also try to update packages that fail and say:
Unable to resolve dependencies. 'Xamarin.Android.Support.v7.CardView 23.4.0' is not compatible with 'Xamarin.Forms 2.2.0.43 constraint: Xamarin.Android.Support.v7.CardView (= 23.3.0)'.
And deployment error after successful build:
The $(TargetFrameworkVersion) for Xamarin.Forms.Platform.Android.dll (v6.0) is greater than the $(TargetFrameworkVersion) for your project (v4.4). You need to increase the $(TargetFrameworkVersion) for your project. Squared C:\Users\USER\Repositories\SOLUTION\PROJECT\PROJECT.csproj
These errors occur for several packages at the same time.
I would like to keep my framework as follows: 
I think my next step is to try changing the version of Xamarin.Forms.Platform.Android.dll, but I'm not sure how to do this.
xamarin xamarin.android xamarin.forms
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