Meet the Vaavud Wind Meter: a portable device that lets you measure wind speed and direction using your iPhone or Android device. The developers are using an optical sensor that measures 40k times per second to detect speed accurately. The device is pretty easy to use. You just have to attach it to your phone, and you are ready to measure wind speed and direction on the go. The companion app provides you with crowdsourced live maps, real-time graphs, and your personal measurement history.
The Vaavud Wind Meter will be compatible with iOS 7 and Android 4.0 or later devices. Like what you see here? You may want to support these guys on Kickstarter.