For an excellent weather reporting tools for tablets and smartphones try weatherbug by Earth Networks. I have used it on all my devices (4) for the past 4 years.Never a problem. It is free with a few ads, or buy the ad free version for less than 5 dollars.
It includes 7 day forecast, radar views, pollen counts, lightning counts, weather alerts, etc.
http://weather.weatherbug.com/mobile.html