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Flash SMS

In this article

Flash SMS, also known as Class 0 SMS or Flash Messages, is a type of SMS (Short Message Service) that is displayed directly on the recipient’s mobile screen without being stored in the inbox. Unlike regular SMS messages that are saved in the inbox and can be read at any time, Flash SMS messages are typically displayed immediately upon receipt and often override other activities on the recipient’s device screen.

Here are some key characteristics and uses of Flash SMS


Flash SMS messages are highly visible as they appear on the recipient’s screen instantly and prominently, usually on top of any other content. They are difficult to ignore as they demand immediate attention.


Flash SMS messages are not stored in the recipient’s inbox or message log by default. Once the message is dismissed or the screen is closed, the Flash SMS is usually not accessible again.

Limited Length

Flash SMS messages are typically limited to a shorter character limit compared to regular SMS messages. This restriction ensures that the message content fits within the limited screen space available.

Emergency Alerts

Flash SMS is often used for emergency alerts, critical notifications, or important announcements that require immediate attention. Examples include severe weather alerts, public safety announcements, or urgent system notifications.

Marketing and Promotions

Some businesses and organizations may utilize Flash SMS to deliver time-sensitive marketing messages, promotional offers, or exclusive deals. The immediate visibility of Flash SMS can increase the chances of the recipient noticing and acting upon the message.

User Interface (UI) Testing

Flash SMS can be employed during user interface testing or for diagnostic purposes. It allows developers or testers to display messages on mobile screens temporarily for debugging or verifying specific UI elements.

It’s important to note that the behavior and support for Flash SMS messages may vary across different mobile devices and operating systems. Some devices may allow the recipient to save or forward the Flash SMS, while others may automatically dismiss or delete the message after a certain period.

Flash SMS is a powerful tool for delivering urgent or attention-grabbing messages directly to the recipient’s screen, ensuring high visibility and immediate awareness of the message content.

Flash SMS

Can anyone send Flash SMS?

The ability to send Flash SMS messages depends on the capabilities and restrictions imposed by the mobile network operator (MNO) and the recipient’s mobile device. In general, not all devices and networks support Flash SMS, and the availability of this feature can vary.

Can anyone send Flash SMS?

it is recommended to consult the user manual or support documentation of the mobile device and messaging application being used to determine if Flash SMS functionality is supported. It’s also worth noting that even if the sender can send Flash SMS, the recipient’s device or network may not display them in the intended manner or support them at all.

Overall, the ability to send Flash SMS messages depends on a combination of factors, including the recipient’s device compatibility, network support, and sender’s device settings and capabilities.

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