OmniFocus is described as 'Is designed to quickly capture your thoughts and ideas to store, manage, and help you process them into actionable to-do items' and is a very popular todo list manager in the office & productivity category. There are more than 100 alternatives to OmniFocus for a variety of platforms, including iPhone, Android, Web-based, Mac and iPad apps. The best OmniFocus alternative is Todoist, which is free. Other great apps like OmniFocus are Workflowy, TickTick, Quire and Superlist.