• Before you leave, download your favorite music, movies, TV shows and books to your device. You'll have plenty to keep you entertained on the plane or during downtime.
• Save web articles (like your unread RSS feed) to a service like Instapaper or Pocket (formerly ReadItLater) that will cache web posts to a local app for offline reading.
• When you have a connection before leaving home, use your map application to pull up maps and routes you might need when traveling, then take a screenshot to save to your phone or tablet (remember to zoom in, if necessary). Map routes like from the aiport to your hotel, or from your hotel to a local landmark. You can also save general maps of an entire area, like the area around a cruise port.
• Look up and save images of public transportation maps, like the local train or subway system, for easy (non-touristy) access on your phone.
• Save screenshots of an online map or directory page for big attractions like museums.
• Get your inbox offline. Copy and paste (or take a screenshot) of important emails like your airline confirmation, or save the entire contents of your inbox with an app like iMail Pro.
• Think ahead and save contact information and addresses for the places you'll be going. Start with your hotel and the airport, plus any attractions (like museums) you're planning to visit. You can copy/paste their info into your notes app for later.
• If your travels take you to a new country with a new language, pre-translate key phrases to help get around. You can save them to a Notes doc on your phone, or use the Google Translate app. Google Translate pulls translations from a server on the Internet, but here's an offline trick: Translate caches the translations that you've already made. If you can anticipate words and phrases that you might need to translate, do it before you leave home while you have a connection, and then they'll be there for you to look up when you need them.
(Image: Flickr user Tourist Republic)