Petal is licensed to you under Apple's Licensed Application End User License Agreement (the "Standard EULA"). This page exists so the App Store has a single address to point to; the Standard EULA is the licence.
The Terms of Use add the details specific to Petal, and the Privacy Policy describes how the app handles data. If anything in those documents conflicts with the Standard EULA, the Standard EULA controls.
This licence is governed by the laws of the State of Maryland, United States, and any dispute about it belongs to the state and federal courts located in Maryland, subject to any rights you have under the law of your country of residence that cannot be waived by agreement.
Questions about the licence: support@twofox.app.