The Independence Day holiday week is upon us, and millions of American families are heading out on the open road. Where past generations depended on paper maps and Mad Libs, the march of technology has given us new tools for kids and parents alike. Our five-plus apps for road trips are accompanied with standbys and alternates to match up with your specific travel needs. Got other favorites or recommendations? Give them a shout out in the comments.

When I was young, in the pre-cellphone days, our road trips with other families included walkie-talkies or CB radios to help coordinate bathroom stops or route changes. Even with iMessage and hands-free headsets, there's something to be said for the one-button convenience of push-to-talk -- just ask the crowd of satisfied and loyal Nextel users who depend on the technology every day. Three popular apps that simulate the PTT experience on the iPhone are Voxer, HeyTell and Zello (all free).

All the walkie-talkie apps offer one-to-one or group voice chat at the press of a virtual button. Voxer's got Facebook integration and a rapidly growing userbase, plus photo and text sharing (and some hefty funding); Zello's got a simple UI including "one big button" for PTT conversations with the other cars in your convoy; and HeyTell's got geographic indicators for your chat partners plus in-app purchases for fun items like voice changers. Any one may save you some dialing and phone calling while you're looking for your next pitstop, so consult with your fellow vacationers and settle on the one you like.

Eyes on the road, please! If you want to automatically alert your friends or family at your destination that you're making progress, check out the free En Route! or the $0.99 just-released