Utilities: The second most obvious answer are the basic utilities the phone can provide such as flashlight, camera, world clocks, etc... These can be very beneficial when caught in a jam.
Currency Converter: This lovely app is extremely handy when traveling for obvious reasons and consequently is a must for any traveler (frequent or otherwise). Although it does use the internet to download daily up-to-date rates, it will work just fine without it.Instapaper: This is one of our favorite apps and one of the most crucial in the arsenal of a subway commuter. While at work or home, find and download websites onto your Instapaper app which will beautifully format it for optimal reading. Then, when you’re underground (or wherever you may be) simply open the downloaded website and begin reading where you left off earlier. It is so simple and so elegantly designed, we think it is a great app to have for anyone who well... reads websites (and we have a feeling there might be a good amount of you out there).
Exit Strategy, iBART, London Tube, etc..:Thankfully, there are many subway apps available which do not require the internet to function. Although we haven't researched it fully, it seems all major American subway lines are covered out there. Just google search “*your city name* subway app offline” and it should turn up. These hand dandy apps usually give you subway maps and other pertinent information like where to board the train or the exact location of subway entrance from the street as well as popular landmarks around town.AllofWiki Offline: Yup. This app does exactly what the namesake promises. Download the entirety of Wikipedia to your phone so you can view it anywhere. But that’s not all! The app comes with additional functionality such as bookmarks, instant searching, random articles, history, font size adjustment, and more.