Why Are My Mobile Push Notifications Delayed?

If you’ve noticed that push notifications from iPresso are reaching your users with a delay, there are several technical and system-related reasons that could explain this. Below are the most common causes, primarily related to mobile device settings and the behavior of operating systems.

1. Battery Saving and System Optimization

Modern smartphones running Android and iOS aggressively manage energy consumption, which can significantly impact the performance of push notifications.

• Power Saving Mode: When the phone’s battery is low, the system limits background app activity, which can delay real-time notification delivery.
  
   
• Adaptive Battery (Android): This feature analyzes which apps are used the least and restricts their ability to wake the system to deliver notifications.
  
   
• "Deep Sleep" Apps (Android): Some manufacturer-specific systems like Samsung One UI or Xiaomi’s MIUI may automatically put infrequently used apps into deep sleep mode, which prevents them from receiving notifications.
  
   
• Focus / Do Not Disturb Mode: If these modes are activated by the user, notifications may be temporarily silenced or completely blocked until the modes are turned off.
  
   

2. Network Connectivity Issues

A stable internet connection is essential for the immediate delivery of notifications.

• Weak Wi-Fi or Mobile Data Signal: To continuously receive push notifications, the device must maintain a constant connection to the relevant services (APNS for Apple, FCM for Google). Connection drops can lead to delays.
  
   
• Network Restrictions: Some Wi-Fi networks—especially public or corporate ones—may block ports required for push services to function.
  
   
• Using VPN: Virtual Private Networks can affect data routing, which may increase the time it takes for notifications to be delivered.
  
   

3. How System Notification Services Work (APNS and FCM)

Notification delivery doesn’t happen directly from iPresso to the user’s device—it is facilitated by dedicated Apple and Google servers.

• Apple Push Notification Service (APNS) and Firebase Cloud Messaging (FCM): Notifications are first sent to Apple or Google servers, which then relay them to the user's device. Although rare, technical issues or heavy traffic on these servers can cause global delays.
  
   
• Notification Batching: Operating systems, in an effort to save battery, may batch less important notifications and deliver them at specific intervals instead of in real-time.

Summary

Delays in delivering mobile push notifications are most often caused by local settings on end users' devices — ranging from power-saving modes and weak network connections to how the system's notification services operate. It is advisable to inform users to check their app settings, battery-saving modes, and ensure that iPresso is not being restricted by the operating system.

If notifications still do not function properly after addressing the above factors, please contact our technical support team.