iMessage Internationally To Android

Hi everyone,

so I recently made a friend in the United States and wanted to text with them through iMessage but they have an android phone while I have an iPhone.

i know that if you’re using I message with others who have an iPhone as well internationally over internet you will not receive charges but I was wondering if the same thing apples for Android.

Like if I am on wifi messaging to a friend who has an Android phone. Will it be free as well or will it get charged?