Voip Push notifications missed delay

I can't explain why but I do experience similar issue, in our test we found that 11.2.2 it is receiving without issues the voip notification, our app wakes up on background correctly.

The difference is that we only experience the issue of never receiving the voip notification when the phone is running on 11.2.5, the same device that was receiving correctly on 11.2.2 after the update to 11.2.5 it stopped waking the app.

Our test initially was focused on different carriers but the real difference seemed to be the iOS version, if the phone was on wifi or connected to debug (Xcode or iOS Console), the voip notification comes correctly.

I'll keep track on this issue and let you know if we found something as workaround.

Hey parapakura,

We are experiencing the issue of never receving the VoIP notification when the Phone is running on 11.2.6 once app is running in background for a extend time.

We have never received this report from customer on any other iOS version.

Do you find any issue or solution on this one?

Please update your finding. Thanks,

Were any of you ever able to resolve this? I've run into an issue where sometimes everything works correctly.... I can recieve a voip push in the foreground, background, or if the app has been swipped away. But then sometimes (roughly 50% of the time) I send a voip push, and the app doesn't wake up at all. When that happens, I have to run the app to see the voip push finally come through. I'm testing on iPhone 8 and iphoneX with iOS 11.3.1.... Oddly enough, testing on an iphone7 it works 100% of the time.

Seems like push are getting almoust everytime, the difference seems to fall on processing power of the device.

If app is not running and gets woken up by a voip push, the didFinishLaunching delegate can be distinguished from a start of the app by tapping on the icon by using

application.applicationState == UIApplicationStateBackground

if this is the case, the information that we are loading for our app is now minimal.

If a device is fast enough our app will do all the actions on didFinishLaunching the push was being received. if the device is old or the actions needed to set up the application are long, seems like watchdog was stopping our app sooner than what we would expect, so the design of the app needed to change to do minimal actions enough to do our voip registration and live enough for the didReceiveIncomingPushWithPayload delegate to be called.

don't forget to use the

withCompletionHandler parameter in order to let apple know that app finished doing its job.

Additional design changes include using "Fetching Small Amounts of Content Opportunistically" (https://developer.apple.com/library/archive/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html)

-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler

where you download information using

NSURLSession

This issue was a pain for so long, and not redesigning our apps (almost from scracth) to improve as much as apple wants may become a real issue for many devs.

I see the same behaviour. And that behaviour could change after removing and installing the app again. The device versions and OS versions varies. There is no structure there. We now have about 500 voip calls a day and about 20% of these are failing bacause the push notification could not be handled. That's way too much!

Hello! Maybe someone decided this problem ?

Hello! I am facing this issue in my app as well.

Sometimes the Voip push is not received at all, but backend receive 200 when they send push.

Is anybody able to solve this?