What is a garbage collector in the context of Android application development?

Garbage Collector (GC) in Android is an automatic memory management mechanism that frees memory occupied by objects that are no longer used by the application. This helps prevent memory leaks and crashes due to memory overflow.

In earlier versions of Android, the Dalvik virtual machine was used, which employed a reference counting garbage collector with periodic cleanup. Starting from Android 5.0, Android Runtime (ART) is used, which improved GC performance and efficiency.

GC runs in the background, tracking objects that have no references and freeing their memory. For developers, this means they don't need to manually free memory, but it's important to write code that doesn't create unnecessary objects or hold references to unneeded data so that GC can work effectively.