From JDC Electronic SA:
The SKYWATCH Windoo measures accurately the wind speed, the temperature, the humidity and the pressure with your iPhone or your iPad!Your device for all outdoor activities: sailing, kite surfing, windsurfing, paragliding, paddling, hikingThe device doesnt have any battery and has to be plugged into the headphone jack. The device needs that audio output level is at the maximum. If not, the application will ask you to push up the volume.3 steps to have your local weather on your iPhone or iPad: 1. Get a SKYWATCH Windoo on windoo.ch or by a JDC distributor (www.jdc.ch/distributors) 2. Download the Windoo application 3. Connect the Windoo to your deviceGeneral features: Instant measurements Graphical display of measurements Measurements history Share measurements on Facebook, Twitter and windoo.ch Display of all measurements on a map Wind speed units: km/h, m/s, fps, mph, knots, Beaufort Temperature units: C, F Pressure units: hPa, mbar, inHg Modes: instant, minimum, maximum, average Available languages: English, French, Japanese, German and ChineseWindoo 1 features: Wind speed Wind direction Temperature, wind chillWindoo 2 features: Wind speed Wind direction Temperature, wind chill Humidity, dew pointWindoo 3 features: Wind speed Wind direction Temperature, wind chill Humidity, dew point Pressure (QFE, QNH), altitudeCompatible with iPhone 4S or newer and iPad 2 or newer. iOS 6.0 or newer is required. The application is not working on iPhone 4.