So I’m going to Stockholm next week and found this while looking for things to do there. It’s a spoken city guide that you access from your phone. You buy a map that shows the locations that are covered and when you arrive at one of the locations you dial in to the service to listen to the description. The cool part is that you don’t pay for the mobile call - even if you are roaming with a foreign SIM card. They can do this because the service is run in conjunction with Telia, one of the mobile networks in Sweden. As long as you make sure you roam onto Telia and not another network, they won’t charge you for calls to the TalkOfTheTown number, and won’t route calls to that number back to your home network like they would with any other number.