In some platforms (e.g. Android), the Button has a default Padding that is irremovable without a custom renderer.
Please add a Padding property to the Button view (or preferably to View itself), so that we're able to customize the Padding manually.
Santosh Latpate commented
I tried it with custom render but not able to remove the default Padding.
Shimmy Weitzhandler commented
Please vote here: https://github.com/xamarin/Xamarin.Forms/issues/1702