This is a special APK for testing pre-release versions of ASTRO File Manager. It can be installed alongside the regular version of ASTRO without interfering with it.
From version ASTRO File Manager BETA 7.2.0.0007:
Security patches and various bug fixes
Variant
Arch
Version
DPI
(Android 5.0+)
Latest: 7.2.0.0007 on December 17, 2018
All versions