Here are his reviews of three apps he suggests for fellow smartphone owners who want to track approaching weather. (He used the iPhone version of all three apps.)
RadarScope ($9.99, iOS & Android) - This is by far the best radar app I have found for the iPhone. This app will show you current weather warnings nationwide, and if you click on a certain warning it will take you to the current radar for that region. It will also provide storm tracks and warning polygons. This app has a one-time charge of $9.99, but if you love to follow weather, it is very much worth it.
Weather Alert USA ($3.99 iOS) - This app will give you a lot of options, including radar images, forecast maps, seven-day outlooks with high and low temps, wind speeds, dew points and humidity, plus much more. You can set up multiple locations for various cities so that you can help keep family members that live in other states informed on approaching storm systems.
iMap Weather Radio: ($9.99 iOS & Android) - This app could be very important when it comes to saving your life if a tornado warning is issued for your county. You can set up to 5 locations, including your current location. When weather warnings are issued for the county you are in, the app will send a text warning to your mobile device warning you of the approaching weather. You can also see the current radar for that county.
The neat thing is that warnings will only be sent to you if you are in the warned polygon area. In other words, if there is a tornado warning issued for your county, and the tornado is clipping the southern edge of the county, you will not receive the warning if you are in the northern part of the county. This app actually turns your mobile device into a weather radio. And you can customize it for your personal use in the settings.