UI-Router is a flexible routing library for AngularJS applications that enables complex nested views and hierarchical state management through a state machine approach rather than simple URL-based routing. Developers use it to build applications with multiple simultaneous views, deep state nesting, and sophisticated navigation patterns that go beyond what AngularJS's built-in router provides. It's particularly useful for large single-page applications that require managing multiple independent view regions and maintaining complex application state across different routes.

25 open issues · last updated Jul 21, 2026