Critical Maps is a free GPS-based navigation app for Android that lets you track your location and share it with other users via a map. This app is perfect for group travel, especially when you need to follow a specific route or have a large group of people traveling together.

With Critical Maps, you can see the real-time location of all the participants on the map, which makes it easier to keep track of everyone. The app also has a chat feature that allows you to communicate with the other participants. The chat feature is handy when you need to give directions or ask for help.

The app is easy to use and has an intuitive interface. It doesn't require any special skills or knowledge to operate. All you need to do is download the app, create a group, and share the group link with the other participants.

Overall, Critical Maps is a great app for group travel, especially when you need to navigate together. The app is free to use and has no in-app purchases or ads, which makes it even more appealing.