Can Apple's silent push notifications launch my app in the background?

Question

According to Apple's documentation I can register for silent notification by adding "content-available" = 1 key-value in aps payload dictionary. I want my app to wake up in background when a silent notification arrives. I set App downloads content in response to push notifications value to Required background modes in my info.plist

This is my payload dictionary

{"aps":
      {
       "alert":"Notification alert","badge":1,"sound":"default","content-available":1
      }
}

I am getting callbacks in -(void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler while my app is in background. But my question is can we get callback to this or any other method when our application is in killed state?

I don't want my app user to see the notification but I want my app to perform certain task by waking it up in background through silent notifications.

Any suggestions would be appreciated.

Answer 1

When the device receives a push message with content-available set, your app gets launched in the background by Apple. Users won't be aware of it. From the docs:

content-available: Provide this key with a value of 1 to indicate that new content is available. Including this key and value means that when your app is launched in the background or resumed, -application:didReceiveRemoteNotification:fetchCompletionHandler: is called.

Also from docs

didReceiveRemoteNotification: However, the system does not automatically launch your app if the user has force-quit it. In that situation, the user must relaunch your app or restart the device before the system attempts to launch your app automatically again.