RiverGuide App for IPhone/IPod Touch
This application is simply sublime. It's $4.99 and is pure and straightforward. You select region of country--in my case Midwest--and you look by state and you will find every river gauge in the state, up-to-date for flows, with historic highs and lows and other pertinent data. In IL there are 213 gauges. Instantaneous reading, plus daily stream chart and weekly stream charts are up-to-date.
No more logging into archaic website every time you wish todetermine if a river is paddleable. Above is the Macworld review. Excellent use for the five dollars that's burning a hole in your pocket.
Sometimes, you just gotta know how high that river really is....