Agile UI is a stand-alone framework that implements all the necessary components to build fully-featured and interractive user interface for your PHP application. Developed by Agile Technologies
License: Open Source
Agile Toolkit is a more feature-rich framework with built-in ORM and a templating engine, making it suitable for complex applications, while CodeIgniter is lightweight and easier for beginners, focusing on rapid development for small to medium-sized projects. The choice between them largely depends on the project's complexity and the developer's experience.