借助谷歌地图API V3 不需要键

V2一样，但是，你只能使用它这是免费的，可公开访问的应用程序。如果它是一个商业产品，你需要谷歌地图API premier

Like V2, however, you can only use it for applications which are free and publicly accessible. If it's for a commercial product, you'll need the Google Maps API Premier