How do you use your iPad (or tablet) when traveling that makes it worth packing along?
First, how do I use my tablet, (not iPad, 'cause iPad has an almost unusable "virtual" keypad? And if I had to bring along a separate keyboard, an iPad would probably be more trouble than it was worth). Then I might use a smartphone, but hate it.
Travel info: All the information (itinerary, maps, accommodation information and reservations, rail schedule and prices, etc) that I have stored in preparation for the trip is on one big spreadsheet, which I can easily view on a tablet or netbook screen.
e-mail: I found out years ago, that using a phone to keep in contact with people back home is cumbersome. Because of the time difference, it seems like whenever I can talk they want to either go to sleep or are in a hurry to go to work. E-mail works great - I can write an email when I have time and they can read it at their leisure when they have time.
financial: My expenses, again, are all kept on a spreadsheet, using a format that companies required me to use when I was working. This allows me to accurately estimate expenses for my next trip. I also keep a "filled-in" spreadsheet with my known and anticipated expenses. I remove expenses when they are paid; near the end of my trip, I have an accurate estimate of what I need to take from the ATM to finish my trip.
Journal: I usually keep a journal of my trip, which I add to in my room at the end of the day.
I have to admit that my M.O. is somewhat influenced by the fact that I am retired and at home 23/7, where I have a powerful desktop computer connected to the internet, a 32" monitor, and a real keyboard (I touch-type). I do all my planning on this system and then transfer the file to my netbook/tablet before my trip. At home, my primary use of my cell phone is for making emergency calls when out-and-about.
To me, "smart" phones are just poor substitute for real computers. I would rather carry an extra pound or two than settle for an inferior substitute.
When I got my Transformer pad, my thought was that I could leave the keyboard, which just snaps on and off, in my room and use it as a pad when out-and-about during the day, but still have the keypad at night to do my "homework". I quickly concluded it wasn't worth a pound saved in my carrying case not to have the keyboard with me during the day.