OMXPlayer is a commandline OMX player for the Raspberry PI.
It was developed as a testbed for the XBMC Raspberry PI implementation
and is quite handy to use standalone.
OMXPlayer can not be used with the KMS driver on Ubuntu Core, make sure
to comment "dtoverlay=vc4-kms-v3d" in /boot/uboot/config.txt (note that
this in turn disables support for mir-kiosk). It is also recommended to
set "gpu_mem=128" (or higher) when playing 1080p60 video.