al and Four Seasons by embracing location-based services to offer consumers hotel deals.The Starwood-owned chain said December 10 that it would offer a 20 percent discount at its bars to users who ???check-in??? for the first time using Foursquare.Checking-in is used not in the traditional hotel sense, but to describe location-sharing using a smartphone and services such as Foursquare or Gowalla.