The deal with Signature Pad

I tried to install the "Signature Pad" component, but when I tried to in Android this message pops:

Adding SignaturePad.Xamarin.Forms.PCL...
Attempting to resolve dependency 'Xamarin.Forms (≥ 1.5.1.6471)'.
Attempting to resolve dependency 'Xamarin.Android.Support.v4 (≥ 23.0.1.1)'.
Attempting to resolve dependency 'Xamarin.Android.Support.Design (≥ 23.0.1.1)'.
Attempting to resolve dependency 'Xamarin.Android.Support.v7.AppCompat (≥ 23.0.1.1)'.
Attempting to resolve dependency 'Xamarin.Android.Support.v7.CardView (≥ 23.0.1.1)'.
Attempting to resolve dependency 'Xamarin.Android.Support.v7.MediaRouter (≥ 23.0.1.1)'.
Adding 'Xamarin.Android.Support.v4 23.0.1.1' to Handwriting.Droid.
Could not install package 'Xamarin.Android.Support.v4 23.0.1.1'. You are trying to install this package into a project that targets 'MonoAndroid,Version=v2.3', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.

I really need help, please. Thank you in advance.