Things 3

$9.99 Made for iPhone, iPad

Things is one of the most popular task managers, both for office work and personal events such as holidays and parties. It includes a handy calendar and To Do lists, but its main strength is the ability to create projects with a series of set goals, and to specify the steps needed to complete each goal. It works with Siri too, so it’s easy to say “buy more wine” as ideas pop into your head.