Kodi - Kodi is an award winning free and open source media player that got its start on the Xbox console.
PseudoTV - PseudoTV Live is channel-surfing for your media center.
Android TV - Android TV is a version of Android made for TV's
Enna - Enna is a Media Center application.
Tvheadend - Redmine
OSMC - OSMC is a free and open source media center built for the people, by the people.