We used the Shaka app for the Road to Hana in Maui. So glad we did because even though I had researched and knew a little of what to expect, that road is a little crazy. The guide was very helpful in making us feel like we weren’t missing out and knowing when to stop. It was easy to use and we enjoyed the upbeat narrator, the music, and found the history on the stops informative. When the tour ended, we were kind of sad not to have our guide for the rest of our trip! Easy to download beforehand since cell service is very limited on the Hana Hwy. It’s also very flexible. We did the road over two and a half days and the tour was for one day. We just stopped and started it as we wanted and it never had a problem knowing where we were.