Final answer:
The methods onSaveInstanceState() and onRestoreInstanceState() are used to save and restore the state of an activity or fragment in Android development when it is destroyed and recreated. Developers would override these methods to preserve important data or save the state of user interface elements. By doing so, they ensure a seamless user experience.
Step-by-step explanation:
In Android development, the methods onSaveInstanceState() and onRestoreInstanceState() are used to save and restore the state of an activity or fragment when it is destroyed and recreated, such as during screen rotation or when the system reclaims memory.
Developers would need to override these methods when they have important data that needs to be preserved across configuration changes, or when they need to save the state of user interface elements, such as checkboxes, text fields, or scroll positions.
By overriding these methods, developers can save the state of their app's components and restore it later, ensuring a seamless user experience.