Shralptide : iphone Tide chart
I fish a lot and knowing the tides is pretty useful. One free iPhone app I have been using has been very good, it's called Shralptide.
One nice function is that when you turn the iPhone sideways, a graphical picture if the current tide is displayed.
I like the simple and graphical interface. You can also use GPS to determine your location.
There are a lot of tide apps but this is the best free one I have used.
;-) Blogging with my iPhone