Some large apps use the XAPK format , which bundles the standard APK with OBB (data) files; these require a special installer like those found on APKPure.
However, it is highly likely you are referring to (or a specific build of it), which is the most prominent open-source N64 emulator for Android, or perhaps RetroArch . These apps often require "cores" or specific APKs to run. xarg 64 apk