Per Cell Broadcast oder App: Warntag: Empfängt mein Handy das Warnsignal?

During the nationwide test day on September 10, radio, television, internet portals, social media, digital billboards, megaphone wagons, and sirens will serve as warning channels. Smartphones, however, are the most important warning channels. If everything goes according to plan, the smartphone should vibrate, the screen blink, and a loud signal tone be emitted at 11:00 AM, even if the phone is set to silent.

But does this automatically work on every smartphone? Or does one need to download an app beforehand and adjust the settings?

According to the Federal Office for Population Protection and Disaster Relief (BBK), there are different ways to receive the warning signal: Cell Broadcast or a warning app. With Cell Broadcast, the warning message is sent directly to all smartphones without the need for an app or registration. The signal comes from the mobile communication network Cell Broadcast.

For the central component of the warning chain to work automatically, the phone must be switched on, not in airplane mode, and the operating system must be compatible (Android 11 or iOS 16.1). Older devices with an incompatible operating system cannot receive a message from Cell Broadcast. In this case, it is advisable to install the official warning app of the Federal NINA or alternatives like Katwarn or Biwapp.

Users should make sure that notifications are activated and they have subscribed to the desired locations. This year marks the first time that the disarming signal will also be sent via Cell Broadcast at 11:45 AM. To ensure the disarming message actually reaches the recipient, the BBK recommends activating the lowest warning level 3.

Tip: Check if all message types are activated in the phone settings under "Cell Broadcast/ Emergency notifications" (Android) or "Official Alerts" (iOS).