Rex is a free iPhone app developed by Get Rex Inc. It falls under the category of Travel & Navigation, providing users with a platform to discover, keep track of, and share recommendations of places they love with friends.

With Rex, users can conveniently keep track of all the spots they have visited in one place. Additionally, they can easily transform photos from past trips and experiences into recommendations that can be shared with friends. The app also allows users to organize their recommendations into playlists, categorizing their favorite restaurants, coffee shops, hotels, and things to do.

One of the key features of Rex is the ability to follow friends and discover recommendations through their travels. Users can stay connected with their friends' experiences and explore new places based on their recommendations. Furthermore, the app enables users to create lists of places they want to visit in the future, allowing them to plan their future travels effectively.

Overall, Rex provides a comprehensive travel map experience, allowing users to see all their favorite places, as well as their friends' favorite places, on a map. It offers a convenient and interactive way to share and discover recommendations, making it a valuable tool for travel enthusiasts.