Until recently, I had thought that I had to have a data connection in order for programs on my iPhone 3G to work that utilize GPS. While I was in Tokyo in May, I had a SoftBank 3G SIM without a data plan in my jailbroken and unlocked AT&T iPhone 3G. As I walked around in Tokyo, I assumed that programs such as Maps would not work. Then, while I was near a big train station such as Shibuya or Shinjuku, I discovered by accident that the "Locate Me" button in a map program worked. That is, a familiar pulsing blue dot would indeed locate me on the map. This phenomenon happened repeatedly. Just to be doubly certain that my iPhone did not have any data connection, I went into Settings > Usage and looked at Cellular Network Data. Both Sent and Received showed 0MB at all times. Recently, I read somewhere that the iPhone would use a data connection to assist GPS when GPS signals are weak or for the purposing of speeding up location acquisition. Therefore, am I correct that, in theory, GPS on the iPhone would locate me on a map wherever I am on earth as long as the iPhone can receive a clear GPS satellite signal?