Which brings me to my one essential iPhone App for Paris travel.
G7 (when you speak, it sounds like g-set, though really it is g-sept) is a market-dominating lead generation service for taxis in Paris. Hailing a cab in Paris is tres difficile and quite different from hailing one in NYC. In NYC, you step off the curb and throw your arm in the air or whistle. Unless you look ill or are wearing a Red Sox hat, a NY cabbie will, at some point, stop.
In contrast, however, in Paris, you go to designated spots (the nearest of which may be 5 minutes away by foot, or by stroller, depending on your age). Even then you could end up waiting forever.
When in Paris my good samaritan deed is to tell other American tourists that the current effort they're mounting to hail a cab will fail and they need to walk a few blocks or call G7.
If you stay at a hotel the concierge can arrange for car service but if you aren't doing that, you really want this app. They also have an English language phone number +33 (0)1 41 27 66 99. I like to think that my French is good enough to cal their French language number, but my French really is deplorable.
The car generally arrives in 7 minutes (could that be the "sept" in G7?).
It does cost a few Euros for pre-ordering but it is pretty amazing and very worth it
A few things to note:
--in Paris, when you enter a cab, you must always say bonjour -- it isn't polite to just enter and provide the address. I usually ad a "Ça va?" (the French equivalent of "how's it going?"). Note: when the driver shoots back "Ça va" he's not repeating/mocking; he's giving an appropriate reply ("it goes")
--don't be offended when they don't know where you are going because they pronounce it differently -- I like to show them the address and there's usually this really profound moment of recognition as if they're saying -- "holy cow dude, was that what you were trying to say?"
--if you have more than 3 or 4 people, you may need more than 1 cab
--book well in advance for "rush time" car service (I once stubbornly made my family walk in the rain on Xmas eve for 45 minutes...but that's a much longer story)
--arranging airport pick up is difficult without an account at G7 and you probably don't want or need an account there so plan in advance for that.
--don't get cocky with your French in a cab. I once struck up a conversation in French with an Algerian cab driver. When he mentioned, in French, that the French had crushed his people, I began (in poor French) to speak of the French/Algerian conflict in the 1950s! He quickly, and with some pain, asked why in the world I would mention that when he was talking about the soccer game from last night! Yikes! Humiliating. I apologized profusely, left an enormous tip and shut the hell up. My parting advice, taken from Basil Fawlty: "Don't mention the war. I did once, but I think I got away with it!"
Hope that helps.