AngularJS can securely integrate with a third-party authentication API for user authentication by using standard protocols such as OAuth or OpenID Connect. These protocols facilitate a secure and standardized flow for user authentication, ensuring that sensitive information is exchanged securely between the client-side AngularJS application and the third-party authentication provider. This approach enhances the application's security and provides a seamless authentication experience for users.

In AngularJS, the .config() method is used for configuring a module. The .config() method allows developers to configure the module before it is run. It is commonly used for setting up providers, decorators, and other configuration settings. This method plays a crucial role in the AngularJS application lifecycle and is essential for customizing the behavior of modules.

$broadcast and $emit are methods in AngularJS for event handling. $broadcast dispatches events downwards to child scopes, while $emit dispatches events upwards to parent scopes. Understanding the impact of these methods on event flow is crucial, especially in complex AngularJS applications with nested scopes. Developers need to choose the appropriate method based on the desired event propagation direction.

Efficient scope management in a complex AngularJS application contributes to performance optimization by careful use of the $digest cycle. The $digest cycle is responsible for detecting changes in the application's data and updating the corresponding views. By minimizing unnecessary calls to $digest and optimizing the update process, developers can enhance the overall performance of the application. Understanding scope and its impact on the $digest cycle is crucial for AngularJS performance tuning.

To avoid flickering in AngularJS, expressions within HTML are initially displayed as double curly braces ({{ }}) until compilation. These double curly braces are placeholders for AngularJS expressions, and once the compilation is complete, they are replaced with the actual values. This technique helps improve the user experience by preventing users from seeing the raw expressions before AngularJS processes them.

In scenarios where AngularJS expressions are used for real-time calculations, data binding may introduce performance overhead. This is because AngularJS performs continuous updates to keep the view synchronized with the underlying model. Developers need to carefully consider the frequency and complexity of expressions to optimize performance in real-time scenarios. Understanding the trade-offs in data binding is crucial for building efficient AngularJS applications.

The ng-repeat directive is essential for rendering lists or tables dynamically in AngularJS. It iterates over a collection of items and generates HTML elements for each item. This powerful directive is commonly used to display data from arrays or objects, making it a key feature for building dynamic and responsive user interfaces in AngularJS applications.

In AngularJS, scope broadcasting is done using the $broadcast method. This method allows the child scopes to emit events to their parent scopes. By using $broadcast, developers can communicate between different parts of the application and synchronize data updates. Mastering the use of $broadcast is essential for effective communication in AngularJS applications.

AngularJS handles the conditional display of elements in the view through the ng-show and ng-hide directives. These directives allow developers to conditionally show or hide elements based on expressions evaluated in the AngularJS scope. This declarative approach simplifies the management of conditional logic in the view, promoting a more maintainable and expressive codebase. Understanding how AngularJS handles conditional display is crucial for creating dynamic and responsive user interfaces.

Handling API rate limits is crucial in scenarios where an AngularJS application makes frequent requests to an API. Implementing mechanisms such as client-side caching, request throttling, and error handling can help manage and respect API rate limits. This ensures that the application operates within the allowed usage thresholds, preventing service disruptions and enhancing overall reliability.