Endangered species field guides / apps could be developed to aid law enforcement
AI / radar / radio waves could detect guns, knives, and explosives
Inspirational messages / quotes could be left in highly trafficked areas
Airports could have movie theaters
Historical places could be made into hotels, restaurants, stores, or event spaces
Airports could offer wellness and activity centers, outdoor spaces, indoor green spaces, art galleries, live entertainment, cryptocurrency payment, and/or workshops
Cities could privatize airports
A pitstop "refresh" location could be available to busy travelers or in cities/towns
Robot birds could help end bird strikes on airplanes
CPR training kiosks could be put in high-traffic, public locations
Places could be available for naps or meditation
Breastfeeding rooms or pods could be available in travel hubs and workplaces
Airports could offer fitness options for travelers
Security checkpoints could have information on the estimated wait time
Airport security checkpoints could allow nonallowable items to be shipped