How long does it take for a message from Google Cloud Messaging to arrive on device

Question

How long does it take for a message from Google Cloud Messaging to arrive on a device?

I want to link my door bell with my Android App. The door bell I receive on a

Answer 1

Almost immediately (1-2sec) if phone is active and has stable internet connection. But there is no 100% guarantee. If phone is sleeping it can take time. If you forgot to pay your carrier bills it will never come.