react-native-charts-wrapper/android/src/main/res/layout/circle_marker.xml

A react-native charts support both android and iOS.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">

    <ImageView
        android:background="@drawable/circle_marker"
        android:layout_width="15dp"
        android:layout_height="15dp" />

</LinearLayout>