White Noise Pro is wonderful for letting you get a good night's sleep.

Bookmarking!

I'm another Tripit user. It's particularly good for long complicated itineraries.

We've used a couple of the Approach Guides one to churches inPuglia and more recently throne for the temples in Bagan. I'll be raving about the later in an upcoming trip report!

I also used and liked Eat Rome and La a Fourchette for Paris.

Co-Pilot for excellent voice directions without using data roaming.

I use TripCase quite a bit, used to use Tripit but prefer TC.
XE for currency conversions

ttt

Word Lens converts foreign text to English or vice versa. Sitting in an Italian restaurant with a menu that is only in Italian and you can't read it? Point your phone's camera at the menu and the App will translate it for you.

Skype
Weather App (I use the Weather Channel)
I Rail (rail time table app for Europe)
Google Translate
Paris Metro (valuable app is you are using the Paris Metro System--similar apps for other European Cities)
Google Maps
Google Translate
Roman Numeral Converter (fun when you are in a church and trying to figure out when that King or Cardinal was buried)
On the Menu (translator for food items in French or Italian--but has been a lifesaver)
Currency converter

WARNING--ALL OF THESE APPS CAN COST BIG BUCKS WITH DATA AND ROAMING CHARGES IN EUROPE. Read up and check with your carrier on data and roaming charges (and plans) when in Europe.

Thanks, Jo, for clarifying regarding the costs of data and roaming charges. Last year I took my iPhone to Germany, but kept it on airplane mode and only used it for the camera. Loved that, but would like to use some apps if it didn't cost in charges. Are there any that do not roam and cost you money?

Jump -- I've used Word Lens for a few years and its still like magic to me!

Ifnotnow_when -- many apps mentioned can be used offline and all can be used with wi-fi. When you know you're in range of wi-fi you can use it. Alternatively you can unlock your iPhone and buy a local SIM card with a bucket of data. It's usually very reasonable in Europe -- e.g. I paid 25E for an Italian SIM card which came with 250 mb data per week for one month plus voice (last year).

DBahn

My best travel companion, I simply can't travel without it.

marking for reference

Bookmarking - this is a great post!

I like Rome2Rio

Elizabeth_S,how do you "unlock your IPhone". Is it something you can do yourself or does your server have to do it? Also, How do you know what apps can be used offline? I'm terrified of turning on my phone and eating up data.

Pawleys - I unlocked my phone with my wireless carrier (and paid a fee to do so). I believe some of the US carriers do it for free once you are into your contract - so I'd check with your carrier. Once it's unlocked you can swap SIM cards everytime you travel - very handy.

(another thing - if you have T-Mobile they have dramatically reduced/waived roaming charges for voice and data so you may not have a need for a local SIM)

Re how to know which apps can be used offline. It's a bit trial and error. I looked at the iTunes descriptions of many of my travel apps - some of them say "offline" for content but others aren't clear. There are practical indications - for example if it says "GPS can track your location in real time" that's an online app. If it's a free app you can download it and test it (turn on Airplane mode and see if it works).

Natwest banking app - lets me move money between accounts wherever I am.

Paypal - ditto

Appropriate tube or metro status apps

Flickr

Various live messaging services to keep in touch with pals.

PS Google maps is a given...

Marking

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