Mashable composite, images courtesy of RoadNinja
Billboards become redundant with the free RoadNinja app — users learn the locations of restaurants, gas stations and points of interest near every highway exit. View real-time gas prices and access RoadNinja special offers and coupons.
Mashable composite, images courtesy of HotelsByMe
Plans changed last minute? The HotelsByMe app can help. Offering real-time availability and hotel pricing in your area, this app pulls hotel ratings from TripAdvisor. So, you’ll know whether the “Five-Star Inground Pool” is actually a four feet-deep mosquito habitat lorded over by a territorial Canadian goose.
Image courtesy of Roadtrippers.com
Take the road less traveled with this app, which finds obscure small businesses and attractions on your custom vacation routes. Roadtrippers — both a web and mobile app — gives you a localized road trip, for a more adventurous feel.
Image courtesy of OpenTable
Make a dinner reservation while you’re still stuck in traffic three states away, with the OpenTable app. Restaurants opt in to the service, often providing menus, photos and more. You can search for available locations by price, cuisine and rating.
5. Field Trip
Image courtesy of Google
This free Google app runs in the background of your smartphone, alerting you to locations fit for a field trip: historical sites, architecture, entertainment, etc. The app talks about interesting places as you drive by and will customize recommendations based on your “thumbs up” or “thumbs down.”
If you have an Android, you have battery problems — this is a fact of life. If you’re taking a long road trip and haven’t invested in a car charger, BatteryGuru can help. After a few days of “learning” how you use your smartphone and data, the app creates a customized battery optimization plan that’ll give your phone a bit more juice.
7. Project Noah
Image courtesy of Project Noah
If you have any science lovers on your road trip, use Project Noah, a great app for discovery. Just upload a picture of a cool specimen, tag your location and it will document in the huge, crowdsourced science experiment that is Project Noah. You can also view any recent documentations near your area or filter based on organisms that interest you.
8. Sky Map
Image courtesy of HDRshooter.com
Decided to pass up the hotel and camp out for the night? Use this educational app to search for stars — as you see them. Sky Map uses GPS data, compass data and date/time to display planets and constellations viewable in your location. A similar free iOS app called Star Chart is available in iTunes.
Image courtesy of Postagram
Want to keep family and friends up to speed on your road trip? This free app sends customized postcards anywhere in the U.S. for $0.99 ($1.99 for addresses outside the U.S.). You take the picture, write the message and the app sends your creation anywhere you’d like.
10. The Traveler
Image courtesy of The Traveler
The Traveler app organizes, documents and stores your trip all in one place: a virtual road trip scrapbook. When you capture photos and videos, the app will add corresponding markers to your map. Compatible with the newest version of Google Maps, it takes pictures through the app’s action bar.
Know of any other great free road trip apps? Tell us about them in the comments.