Smitten with Samsung's Galaxy S 4? Well, if you're looking to pick on up right now, you'd best book a red-eye flight to South Korea, where it'll go on sale in the next 24 hours. The 5-inch 1080p flagship will arrive on all three of the country's main carriers, with an unspecified global roll-out following on Friday. Meanwhile, the company has also commented on "supply chain problems" affecting its roll-out of the S 4. In a statement to Sky News, Samsung said that initial supplies of the handset may be limited "due to overwhelming global demand" and its limited stock of memory components. The pinch is already being felt in the US, as both Sprint and T-Mobile reassess their launch dates in-store.