As you may know, Sopcast is needed if you want to watch TV channels online. Actually, it is the best player (as I know of) that allows you to watch online television channels.

The latest version available is Sopcast 0.8.5, which has been released a while ago. Recently, its PPA has received packages for Ubuntu Vivid.
Installation instructions:
Up to date packages are available via some third party PPA, so installing the software on Ubuntu systems is easy. Just add the PPA to your system, update the local repository index and install the sopcast package:
$ sudo add-apt-repository ppa:lyc256/sopcast-player-ppa
$ sudo apt-get update
$ sudo apt-get install sopcast-player
Optional, to remove sopcast-player, do:
$ sudo apt-get remove sopcast-player
The installation instructions should work on Ubuntu 15.04 Vivid Vervet, Ubuntu 14.10 Utopic Unicorn, Ubuntu 14.04 Trusty Tahr, Ubuntu 12.04 Precise Pangolin, Linux Mint 17.2 Rafaela, Linux Mint 17.1 Rebecca, Linux Mint 17 Qiana, Linux Mint 13 Maya, Pinguy OS 14.04, Elementary OS 0.3 Freya, Elementary OS 0.2 Luna, Deepin 2014, Peppermint 6, Peppermint 5, LXLE 14.04 and Linux Lite 2.