A recent iOS update has given developers the ability to send SMS alerts to iPhones. This capability, called “Critical Messages,” is designed for highly important, time-sensitive notifications. Apple’s documentation says that this function is intended for specific situations, such as enterprise check-ins from employees working in hazardous or remote locations, or when an employee is unable to access their iPhone.
To prevent abuse, Apple has implemented strict conditions for the use of Critical Messages. These conditions include restrictions against sending unsolicited messages, phishing, or spam. Apple specifies that developers cannot engage in activities that violate anti-spam laws or are otherwise inappropriate or illegal.
Users are unlikely to receive Critical Messages frequently. Similar to existing Critical-level notifications, they are meant to be used sparingly for urgent notices. If a user receives unwanted Critical Messages, they can opt out in iOS settings. This can be done by going to Settings, then Privacy & Security, and then Critical Messages. Apps that have requested permission to send these messages will appear here, and the permission can be disabled.
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