OmniOutliner

OmniOutliner is more than just a task manager. With its help, you can also brainstorm new ideas, keep track of your expenses, write screenplays, and even create agendas.
The program's interface is very intuitive, so minimum computer knowledge is required to handle OmniOutliner.

Still, if you require assistance while working with this tool, you can access the integrated help guide which provides you with plenty of useful hints.

You can choose between a wide variety of themes, have the ability to export your notes to your local directories, print a sheet with your brainstorming ideas, and so much more.

The developer lets you choose between 2 types of licenses: Essentials and Pro. The first edition brings you a limited amount of features but comes with a very reasonable price. The Pro version provides you with a wider variety of advantages, such as the support for AppleScript and more output formats (when exporting the stored content), the ability to edit and encrypt the imported documents, option to number rows, etc. However, it's a bit more expensive than the Essentials variant.

In conclusion, no matter which edition of the utility you choose and purchase for your Mac, you will get access to quality services. OmniOutliner is the perfect solution for keeping track of your ideas and to-dos and provides you with many useful features for project planning.