Both Apple and Google mobile notifications are long-lived TCP/IP sockets where the server writes bytes to the stream when it wants to wake up the phone. The TC

Both Apple and Google mobile notifications are long-lived TCP/IP sockets where the server writes bytes to the stream when it wants to wake up the phone. The TCP/IP and protocol-specific handshake is started by the phone, but then the phone just waits to receive data. That counts as fundamentally push, all the way down to the transport layer.