I've previously mentioned that the iPhone's 99 cent Wind Meter App is about as accurate as some $70+ hand held windmeters (though you don't want to get your iPhone wet.) The creators of the app are now proud to announce that they've updated it to work on the new 3GS iPhones as well (it always worked on my 3GS but apparently that was unusual.)
So the update is out there. It now has a display that swings around to point at you if you hold the iphone horizontally and point the bottom of the phone into the wind. I find I get more accurate (ie more like what everyone else's windmeters say) results if I hold the thing perpendicular to the wind, though.
In any event, nothing else in windsurfing costs a buck (what's a downhaul running you these days? And don't be cheap...get the Formuline!)
(The editor gets best results holding the iPhone like so. Photo by Peconic Jeff.)

More importantly, NASA to design a Puffin plane:
http://www.scientificamerican.com/article.cfm?id=nasa-one-man-stealth-plane
Posted by: Brian S | January 20, 2010 at 11:18 AM
I tried Wind Sensor and I find it more accurate. It also has integrated compass which can be used to find wind direction.
http://itunes.apple.com/app/wind-sensor/id398101772
Posted by: Neuman Müller | October 30, 2010 at 01:52 AM
Not sure I am satisfied with this app. I thought I was getting a meter that would calculate actual wind speed in real time. It appears to be giving me a forecast for my locality. Reserving judgement on this app.
Posted by: F. Hertlein | December 25, 2011 at 07:38 PM
Sounds like you downloaded something other than this app...it's a wind meter (that calculates actual wind speed in real time.)
Posted by: Michael | December 26, 2011 at 01:10 PM