> Prior to iOS 10, the only way to display notifications for end-to-end encrypted chat without giving Apple a plaintext copy of everything in the notification w

> Prior to iOS 10, the only way to display notifications for end-to-end encrypted chat without giving Apple a plaintext copy of everything in the notification was to abuse the VoIP feature. It’s not the only way, but VoIP is the most reliable way. You can accomplish the same thing with encrypted silent push notifications, that wake up the app and trigger a decrypted local notification. Problem is that silent push notifications aren’t reliable because they don’t always wake up the app (which is throttled by the OS).