NotifyMe is an event reminder application that utilizes Apple’s Push Notification Service. Whether it be TV Shows or To-Do events, the app will push information at a specified time. With a leaf from Apple’s minimalist tree, this application is almost flawless.

If the iPhone calendar and sheer absence of built-in task management leave you wanting more, check out Pocket Informant from WebIS. It is a well thought out application, adapted nicely to the iPhone. Despite some performance issues and a (current) lack of functionality compared to the more mature versions of PI that exist on other platforms, its active development ensures that this will not be the case for long.

Organizer is useful for writing your daily plans, jotting down your ideas and for an advanced memo tool. The options in this application for making notes are impressive, but lack of calendar integration lets it down.

Appigo Notebook differentiates itself from the competition by offering tight integration with Todo, a task management app also by Appigo. It also offers numerous formatting options, the ability to sync notes with a free online service, full text searching, the ability to create multiple notebooks, and more.

Appigo Todo is a task management app with a streamlined user interface. It includes ways to tag and otherwise set todo items apart, robust search and filtering, and is augmented by several synchronization options as well as tight integration with Appigo Notebook, a note taking app available from the same author.

OmniFocus, the fantastic GTD task manager comes to the iPhone, and it rocks!