One small addendum to my Korean experience is that the supposed automatic recharging of my prepaid data plan with KT didn’t quite work as expected. Sure, it recharged itself twice during last fall, but in December it didn’t do it automatically. Because of the eye surgery, I didn’t really need the phone, so it wasn’t until mid-January that I did something about it. At the KT office the person was very confused and said that it shouldn’t have even worked at all (but it worked twice, October and December), and maybe the problem was that I used a debit card instead of a credit card. Then I took out my Korean credit card, they charged it and it was supposed to work. Come February and the date for the automatic recharge and my phone was again without a data connection, so it didn’t work. This was so close to my departure that I didn’t bother doing anything about it. Bottom line is, sensibly priced prepaid mobile data might not exist with KT after all, or if it does, you need to drop by their office every month to re-activate it.