src/NSWallet/Droid/Resources/layout/Toolbar.axml
<?xml version="1.0" encoding="UTF-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/toolbar" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="?attr/colorPrimary" android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" android:popupTheme="@style/ThemeOverlay.AppCompat.Light" />