Foursquare has released an update to its location-based social networking app adding support for in-app SMS and e-mail messaging and a number of other enhancements. Foursquare users can now send SMS and e-mail messages from directly within the Foursquare app rather than having to exit the application. The update also adds further high-resolution content for iPhone 4 devices, improves support for Fast App Switching and adds a current position indicator…
