A new version of the Nike+ GPS app hit the store today. The interface is redone from scratch matching the design of the also new HTML5-driven website. I love all the changes so far. My favourite is the new landscape history view, where the list of runs morphs into a chart. Seeing this made me want to go for a workout right then:
With this version the app is no longer iOS exclusive, they released an Android application as well. And for a limited time both are free to download, so go grab them while you can.
Update: To save yourself the annoyance, upgrade to 4.0.1 to fix the lock screen / background bug. Thx @verkutya.