Field Trip is a location-based mobile app for Android, that notifies you when you are near locations of interest. . It was created by NianticLabs@Google.
This app will work outside the US, but the info it has is mainly USA based, The Field Trip FAQ had this to say at some point:
Q: Can I use Field Trip outside the US?
The initial launch of Field Trip is focused on the US. There is some information outside the US but not a lot. Stay tuned for more information about international availability.
On November 10, it was updated to include a “Niantic Data Repository” feed which contains locations of various monuments, previously referenced in the Tycho Posters. The descriptions for these contain “Ingress Analysis File” numbers and “XM Ground Truth Sample Point” numbers. When viewing one of these locations, a "portal sound" may play.
Later when Ingress was released on the 15th it was revealed that the “Ingress Analysis File” were actually passcodes.
Location: Marfa, Texas
http://www.fieldtripper.com/c/TU-I5hsYq70/the-chinati-foundation
Location: San Francisco, California
http://www.fieldtripper.com/c/FLvyWzboGy8/
Location: San Francisco, California
http://www.fieldtripper.com/c/YBT_rh1emIA/
Location: Zurich, Switzerland
This is the same memorial as the one shown in poster #5
http://www.fieldtripper.com/c/PPdnipaUIr0/
Location: Geneva, Switzerland
This is the same Globe found on poster #1
http://www.fieldtripper.com/c/YXbTjRww9A4/the-globe-of-science-and-innovation
Location: Podgaric, Croatia
This is the same Globe found on poster #4
http://www.fieldtripper.com/c/QO5hsoSdq8U/
Location: Kabul, Afghanistan
http://www.fieldtripper.com/c/EX27_T0Wd8E/