Silent Background Push Notification not working in Release build.

Hi there,

Our app is installed on tablets provided to customer workers for performing tasks. We're currently implementing Push Notifications using AWS SNS and FCM. The goal is to send data-only (silent) push notifications to trigger a function that creates a record in the app's local DB. This approach allows us to control how the message is displayed in the foreground and background using Notifee. While this works well on Android in all states (foreground, background, killed), we're facing an issue on iOS, specifically in the release build. The silent push notifications only reach devices when the app is in the foreground, not in the background or killed states. Normal push notifications work fine, but we require the ability to send silent notifications for better processing control. Upon researching, we discovered that Apple has strict guidelines for these notifications to prioritize user experience, battery usage, spam prevention, and privacy. However, in our case, the tablets are dedicated work devices with only our app installed.

Given this context, is there a reliable solution to send silent push notifications to iOS devices with the app in the background or killed states?

A background push will never ever get delivered to the app if the app has been terminated. There is absolutely nothing you can do about that. If the app is in the background it should, however it might not if the batter level is low or several other undocumented criteria.

I got this working using FCM and Notifee, but I've tested it on a few devices and it hasn't been 100% reliable. On one device, it works flawlessly in all states (foreground, background, killed) and is able to launch the app in the background after receiving a silent notification. So it is definitely possible... However, it hasn't been consistent across all test devices. One device doesn't wake up when the app is force quit by the user, but works in other cases. It seems like there are just too many variables :/

Apple's documentation even states:

"The system treats background notifications as low priority: you can use them to refresh your app’s content, but the system doesn’t guarantee their delivery."

Anyway, these resources were helpful for me:

Silent Background Push Notification not working in Release build.
 
 
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