What are the advantages and disadvantages of using a single activity in an application?

Using a single Activity in an Android application has its pros and cons.

Advantages:

• Easier to manage navigation, as all logic is in one place.
• Fewer overheads for creating and destroying Activities.
• Simplifies data transfer between screens via fragments.

Disadvantages:

• More difficult to maintain and scale the application if the logic becomes complex.
• Navigation and state management can become confusing.
• Increased risk of memory leaks if fragments are not managed carefully.

Example: an application with multiple screens implemented through one Activity and several fragments that switch within it.

This approach is suitable for simple applications or when flexible interface management is needed, but for larger projects, it is better to use multiple Activities to divide responsibilities.