The new Polkadot Ledger App requires a SignedExtension called CheckMetadataHash to be present in the runtime of a Polkadot-SDK chain to work. If a Polkadot-SDK has this new extension, together with other requirements, then the new Polkadot Ledger App will be compatible. In order to track adoption progress, Metadata is retrieved from all chains daily and queried to check if the new SignedExtension is present. The table will return yes/no depending on if the identifier was found.
Example identifier:
{ "identifier": "CheckMetadataHash", "type": "969", "additionalSigned": "528" }