On Thursday, Apple updated its iOS App Store to offer a special sale on productivity apps, taking 50 percent off highly-rated programs such as to-do list Clear, package tracker Deliveries, and a utility that turns an iPad into a wired second monitor for a Mac called Duet Display. Corresponding Mac versions of the apps are on sale as well, such as task manager Things. The sale, which is expected to last for a week, is a repeat of an earlier promotion along similar lines called "Get Productive."
