The App is Free but some of the tours may have a fee. New tours published every day. Download the App now, then visit the website to find a tour near you. The tours are created by the TourBuilder App. They can include audio and or video commentary, photo's docs and links. You will need an android device with built in GPS to fully experience the tours.
App wouldn't open
I defy you to find a better TourGuide App. This has everything you need and is totally free with no annoying ads.