Maps that highlight waypoints and tooltips from other users (a la Waze). This will ensure the user is heading in the correct direction towards their intended destination and help them take the safest most efficient route.
 

A Library of To Do Lists (a la Thrillist)—This will replace the generic city guidebook feature seen on many websites and travel apps and allow for a more personalized experience.
 

Search feature (a la Yelp) enabling users to search by location and/or category.
 

My Trips feature that allows users to create lists to save places and events of interest.
 

Social feature allowing users to leave comments, reviews, tips, and ask other users questions.
 

In-App Booking and Reservations to allow users to make dinner reservations, buy concert tickets, or book a hotel room, on the fly.