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Nothing - every time I tried it told me it didn't have any information for New Zealand. Apple maps has lousy resolution and points of interest are missing or in the wrong location too so overall not very impressed.
 
Mostly for time and weather.

I travel often and I have to be in contact with many people in different parts of the world (family, friends, work, etc). Time differences can be tricky with daylight saving.
 
If you are bored/lonely you can even talk to Siri as a friend and have a conversation with her... Ask her random questions, math questions, anything you can think of. I think it would be funny to talk to her in public for a long time just to get a reaction from people. Siri can be your friend.
 
I use him to wake me up :D

But wish I could choose between a him and a her...!
 
I use it to set the alarm clock when I am home on wifi and text when on wifi. Other than that, it never works right and just makes me want to throw the phone out the truck window when I have to repeat myself 14 times to get one text message out.
 
I use her/it for Voice Dictation, because i can't spell worth crap.
 
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