iOS/Android push notification integration with Wialon Hosting

I am trying to build a prototype of iOS app which communicates with Wialon Hosting. One of functions is the app can receive the request from Wialon Hosting no matter it is running in foreground, background. If the app is running in foreground, I think Wialon IPS is one way to do that. But if the client is in background, iOS only allows certain type of apps (such as VoIP, content download) running in background.

iOS also supports push notification, which make it possible for the app to receive notification no matter it's in foreground or background or not running. I took a look at Wialon Hosting document and found it supports sending a quest to external system. But there is no much details about this feature, such as how to build the request, header, parameters. I think it's possible to integrate iOS or Android push notification with Wialon Hosting.

Could you give me some suggestions?

Thanks,