The term designates a specific installation package designed for devices operating on a legacy iteration of a mobile operating system. It represents a compiled application file compatible with the second major release of the platform. As an example, a user seeking to run an older game on a vintage device might require this type of file for proper installation.
Its relevance stems from enabling functionality on devices no longer supported by contemporary software updates. It offers access to applications developed during that era, preserving software heritage and allowing continued use of older hardware. The historical context is significant, reflecting a period of rapid evolution in mobile technology and application development.