SDK= Software Development Kit
It means that people can create great native applications for your iPhone.
I never used a SmartPhone before I got my iPhone and I was not sure I would like it. I couldn't text message either
But, I must say that I really LOVE it. I have found it so handy when I am out and about and need a quick map or to check a Website, etc. Since I have an iPod, I don't put my music on it but I do sometimes put audiobooks on so if i am waiting for the children I have something to listen to.
Besides, who needs an excuse to go visit the Apple Store ?!?! We go just to browse on the weekends
Disclaimer: I do work for Apple, but I am on the geeky IS (Information Systems) side of the house, so I am as amazed at what the Engineering teams come up with as anyone.
--Daneen