Google+ is an account service that allows interaction with other users through posts and pictures. This is the official link to upgrade the Google Plus SDK for iOS. Resources include download, access frameworks, upgrade, and build. Additional tools explain how to integrate Google+ into iOS, how to share to Google+ from iOS, and how to share interactive posts from the iOS app.
Sure, you and 20 million of your closest friends are using foursquare. But how useful is it? UK-based Lanyrd, "the social conference directory," recently launched foursquare integration which aims to reward you with more than just points for checking into an event venue. Named after "the thing you wear around your neck at some conferences," Lanyrd offers a user-generated directory of different events, such as technology trade shows, hackathons, and unconferences like BarCamp. Now you can connect Lanyrd to your foursquare account and, after you check in at an event venue, jump over to the Lanyrd mobile app or web site to see more event information.