Cross-Platform Mobile Attestation Normalization

This document defines a set of requirements and a normalized Entity Attestation Token (EAT) profile for representing attestation evidence produced by attestation services across heterogeneous mobile platforms, including platform-specific mechanisms such as Google Play Integrity, Apple App Attest, Apple DeviceCheck, and other OEM- specific or third-party attestation services. The goal is to enable interoperable processing of attestation evidence by verifiers and relying parties without requiring changes to the underlying attestation providers. This document specifies a canonical mapping of platform-specific attestation claims into EAT claims and defines normalization rules intended to improve consistency across mobile ecosystems.