Not exactly a media server but not long ago I've discovered two Android Apps: Wiseplay and Arena Viewer (mostly for sports)
With the first app and a list of channels you've access to tv channels, movies,etc..
I run those apps directly from my mobile phone and I can use it without any lag; those apps comunicates with my Chromecast an that's it: semi-media plex in 10 min !!
Kodi configured the way I like. I once spent a lot of time configuring and modifying XBMC. With Kodi I've not gone to the same extent but it's looking pretty nice. I also have my media server setup in RAID 5 with the files accessible through Windows SMB, Kodi and MediaTomb if I need to transcode for some devices.
The Android version of Kodi is very pretty and fairly fast!