Is there a known alternative hub/protocol to traditional push notifications that would provide 100% guaranteed delivery to an cross-platform app that needs to be in a background sleep state and woke up upon notification receipt or delivered upon device on. I just recently discovered that current cross-platform push notifications via the different notification hubs don't have this capability.
The notifications need to be specific device deliverable with a small payload. The hub needs to be scalable to handle 50M/sec notifications on a global data center network like Azure with device location capabilities like a cell phone network. The app can participate in enabling that capability similar to a mobile phone with its carrier.