Nike+ GPS app, including bug fixes and an auto-calibration feature, which should help improve the accuracy of your run. Also on-board are social features, which push running updates to Facebook and Twitter. The tweets / posts can thankfully be edited before being sent out into the world, but we'd recommend using a bit of discretion before loading up your feeds with the minutiae of your latest workout. The updated app can be downloaded now for $2 from iTunes.
Source : here