I downloaded this per the advice of our local weatherman, who is nothing short of a local legend after 24+ hours solid reporting during the Tuscaloosa tornado of April 28, 2011, a day I will never forget!!
No matter how tech savvy you may or may not be, NOAAWeatherRadio will work for you. It's very intuitive, and has lots of information with networks that span the entire nation, yet deliver accurate and timely local weather. I have alarms set for my location, as well as those of my children, and other relatives who are scattered across the country. The warnings wake me up before any other communication stream. I find NOAAWeatherRadio to be more reliable and user friendly than my NOAA weather radio. All this, and I am using the free version!
If you are worried, as I am, about your cell dying during a weather disaster, just keep a few power banks continuously charged..... you need them anyway. Don't wait.... if I can use NOAAWeatherRadio, so can you.