Foursquare “Radar” Taps iOS 5 to Alert iPhone Users of Local Activities Foursquare has released version 4.0 of its iPhone app with a new feature called Radar that informs users about stuff happening nearby. Radar leverages new functionality available in Apple's iOS 5 SDK -- specifically "region monitoring." Once you opt in to Radar, Foursquare will send you push notifications when you're nearby pl
![Foursquare “Radar” Taps iOS 5 to Alert iPhone Users of Local Activities](https://cdn-ak-scissors.b.st-hatena.com/image/square/251ed64b24581a3ce3eb5d51fa1fcb1c7f34af57/height=288;version=1;width=512/https%3A%2F%2Fhelios-i.mashable.com%2Fimagery%2Farchives%2F036Ft3pVBZtgNwcf4AGWFOm%2Fhero-image.fill.size_1200x675.v1647020318.jpg)