Wow. Sounds like Android is in the lead. I don't want to spend hundreds of dollars on a phone just because it can interface easily with my hobby, but what a bonus! I didn't know there were ready made aps for Arduino! Fantasitc! Thanks for the info.
As a side note, I just learned that iPhone5 can't use data and voice at the same time on the Verizon and Sprint networks...but Android phones can.
If there are any iPhone Arduino lovers out there, speak now or forever hold your peace 