When Foursquare introduced the "all-new" version of its app in June, it added some new features, but also took away the ability to switch between nearby check-ins and all activity. Now, based on user feedback, the company has decided to bring back the functionality with a new update, making it easier to find out what friends who are close by are up to. The update is live for both iPhone and BlackBerry users, while Foursquare says that it will be hitting the Android app "soon." And as with virtually all updates, there's also the requisite design tweaks and bug fixes to look forward to.