Forms is great for developing apps on Android and iOS but it is missing some important features:
PCL and SharedLibrary, multi-screen / multi-resolution image management
HTML formatted text for labels and buttons
PCL and SharedLibrary custom font management
Android developers can use NinePatch bitmaps, the drawable directory naming convention, Html.FromHtml, and a bunch of complex file manipulations to address the image issue. Likewise, iOS developers can use ResizeableImageWithCapInsets, the @2x, @3x, @4x file naming convention, and some 3rd party libraries for this purpose. Forms 9 Patch enhances Xamarin
Forms to make multi-resolution / multi-screen image management, custom fonts, and HTML text formatting easy for PCL and Shared Library apps for iOS and Android.