The app is Clime Pro on iOS, they lock full access to Hurricane Milton data behind a $10 USD per week paywall.
If you’re in the area impacted by Milton, you can find publicly available resources at the National Hurricane Center’s website: National Hurricane Center
To be fair, free broadcast tv and radio is still a thing, and they are an integral part of the US’s disaster alert system. With the right equipment (read: basic cheap radio available almost everywhere), you can still listen to weather information (both general and severe) directly from the horse’s mouth 24/7 for free.
In a disaster situation, these services will still stand because they require less infrastructure per person reached than is required to deliver high-speed internet to the same number of people.
These services still exist, and will continue to, but the knowledge of them has atrophyed from disuse. They won’t go away, they’ve just been replaced in general usage because of the convenience that the internet provides us.
TL;DR: Get you a weather radio, get free weather for the life of the equipment. Even if it’s not your daily driver, get one anyways, because you’ll be able to hear the most relevant info in the worst situation.