The ones I know support bunker style URLs https://github.com/nostr-protocol/nips/blob/master/46.md#direct-connection-initiated-by-remote-signer but we need nostrconnect URL https://github.com/nostr-protocol/nips/blob/master/46.md#direct-connection-initiated-by-the-client support in clients so mobile apps can scan a QR and establish the connection.