The term identifies a specific iteration of the YouTube application packaged as an Android Package Kit (APK). This file format is used for distributing and installing mobile apps on the Android operating system. The numerical sequence indicates the version number assigned by the developers. An example would be using this specific version to potentially access features or interface elements present at that time.
Accessing a particular version allows users to experience the application as it existed at a specific point in its development. This can be important for individuals seeking a familiar interface, or who wish to avoid changes introduced in later updates. Historically, these specific versions might be sought after if they offer performance advantages on older devices or retain features subsequently removed by the developers.