“Prayer for peace in my heart” is partially based on Ephesians 2:13-18 which speaks about how Jesus is our only true peace. He makes peace between you and God by ending all conflict and hostility. But beyond just an end to disagreement, true peace is a unified heart. Pray for peace in your heart and God will give it to you.
Because if you drop your phone and you break it, you wont be able to talk to your friends without actually walking to their house. And you wont be able to access the internet so you would actually have to READ a book!