[strcat]

The official Android Auto app works on GrapheneOS as an extension to sandboxed Google Play. We don't have our own implementation yet and it's not planned in the near term but it is available. Google Pay doesn't allow alternate operating systems but it does work on GrapheneOS from a technical perspective, it just doesn't allow using it in practice without pretending to be the stock OS on a legacy Google-certified Android device without support for hardware attestation. Most banks have their own tap-to-pay implementation in Europe but that largely got phased out in the US.