I have only a basic nokia and use prepaid minutes. $100 per year, I don't use all the minutes because we do only use the phone as a phone.
That said, Ruki's I phone was cool...after dinner, we went to the Hilton's parking garage & she made a quick video of the Bullitt Mustang, me pointing to & explaining features. Started it up, did a bit of revving to record the exhaust tone...Cindy afraid hotel security was going to come. Yep, the Bullitt exhaust is kind of loud in a basement parking garage.
Pretty amazing technology, all those apps. I recently read there is even an app for calculating a bank shot playing pool. Of course, it doesn't take into account the real world variations caused by speed & spin...but it's close.