Overview
- WhatsApp activated the server-side check on Monday, October 5, 2026, that shows a warning and prevents sign-in on devices running obsolete iOS or Android until the system software is updated.
- The enforcement is applied from WhatsApp’s servers so users do not need a new app version; the app simply refuses login on phones whose OS versions do not meet the messenger’s current minimums.
- WhatsApp has said the move targets phones that cannot run the required platform updates, with coverage focused on older Android models and iPhones that cannot reach the app’s stated minimums such as Android 6.0 and iOS 15.1.
- The incompatibility follows a gradual deprecation pattern: first no new app updates, then intermittent failures for messaging and calls, and finally full loss of service, so users are urged to back up chats to Google Drive or iCloud and plan to move to a newer device if needed.
- Meta says the measure defends against attacks that exploit known OS flaws to install malware that can access data before WhatsApp’s end-to-end encryption takes effect, and users with unupgradeable phones face permanent loss of access unless they replace their device.